/usr/bin/java -Xmx8000000000 -Xss4m -jar ./plugins/org.eclipse.equinox.launcher_1.3.100.v20150511-1540.jar -data @noDefault -ultimatedata ./data --traceabstraction.trace.refinement.strategy FIXED_PREFERENCES --traceabstraction.compute.interpolants.along.a.counterexample FPandBPonlyIfFpWasNotPerfect -tc ../../../trunk/examples/toolchains/AutomizerC.xml --traceabstraction.assert.codeblocks SMT_FEATURE_HEURISTIC --traceabstraction.assert.codeblocks.term.scoring.heuristic NUM_VARIABLES --traceabstraction.assert.codeblocks.term.scoring.heuristic.partitioning.strategy FIXED_NUM_PARTITIONS --traceabstraction.assert.codeblocks.term.scoring.heuristic.number.of.partitions 2 -s ../../../trunk/examples/settings/default/automizer/svcomp-Reach-32bit-Automizer_Default.epf -i ../../../trunk/examples/svcomp/recursive-simple/id_o20.c


--------------------------------------------------------------------------------


This is Ultimate 0.1.25-d623d84
[2020-07-21 16:05:29,102 INFO  L177        SettingsManager]: Resetting all preferences to default values...
[2020-07-21 16:05:29,108 INFO  L181        SettingsManager]: Resetting UltimateCore preferences to default values
[2020-07-21 16:05:29,141 INFO  L184        SettingsManager]: Ultimate Commandline Interface provides no preferences, ignoring...
[2020-07-21 16:05:29,141 INFO  L181        SettingsManager]: Resetting Boogie Preprocessor preferences to default values
[2020-07-21 16:05:29,143 INFO  L181        SettingsManager]: Resetting Boogie Procedure Inliner preferences to default values
[2020-07-21 16:05:29,146 INFO  L181        SettingsManager]: Resetting Abstract Interpretation preferences to default values
[2020-07-21 16:05:29,150 INFO  L181        SettingsManager]: Resetting LassoRanker preferences to default values
[2020-07-21 16:05:29,153 INFO  L181        SettingsManager]: Resetting Reaching Definitions preferences to default values
[2020-07-21 16:05:29,155 INFO  L181        SettingsManager]: Resetting SyntaxChecker preferences to default values
[2020-07-21 16:05:29,157 INFO  L181        SettingsManager]: Resetting Sifa preferences to default values
[2020-07-21 16:05:29,159 INFO  L184        SettingsManager]: Büchi Program Product provides no preferences, ignoring...
[2020-07-21 16:05:29,159 INFO  L181        SettingsManager]: Resetting LTL2Aut preferences to default values
[2020-07-21 16:05:29,161 INFO  L181        SettingsManager]: Resetting PEA to Boogie preferences to default values
[2020-07-21 16:05:29,163 INFO  L181        SettingsManager]: Resetting BlockEncodingV2 preferences to default values
[2020-07-21 16:05:29,166 INFO  L181        SettingsManager]: Resetting ChcToBoogie preferences to default values
[2020-07-21 16:05:29,168 INFO  L181        SettingsManager]: Resetting AutomataScriptInterpreter preferences to default values
[2020-07-21 16:05:29,170 INFO  L181        SettingsManager]: Resetting BuchiAutomizer preferences to default values
[2020-07-21 16:05:29,172 INFO  L181        SettingsManager]: Resetting CACSL2BoogieTranslator preferences to default values
[2020-07-21 16:05:29,176 INFO  L181        SettingsManager]: Resetting CodeCheck preferences to default values
[2020-07-21 16:05:29,179 INFO  L181        SettingsManager]: Resetting InvariantSynthesis preferences to default values
[2020-07-21 16:05:29,181 INFO  L181        SettingsManager]: Resetting RCFGBuilder preferences to default values
[2020-07-21 16:05:29,183 INFO  L181        SettingsManager]: Resetting Referee preferences to default values
[2020-07-21 16:05:29,184 INFO  L181        SettingsManager]: Resetting TraceAbstraction preferences to default values
[2020-07-21 16:05:29,188 INFO  L184        SettingsManager]: TraceAbstractionConcurrent provides no preferences, ignoring...
[2020-07-21 16:05:29,189 INFO  L184        SettingsManager]: TraceAbstractionWithAFAs provides no preferences, ignoring...
[2020-07-21 16:05:29,189 INFO  L181        SettingsManager]: Resetting TreeAutomizer preferences to default values
[2020-07-21 16:05:29,191 INFO  L181        SettingsManager]: Resetting IcfgToChc preferences to default values
[2020-07-21 16:05:29,191 INFO  L181        SettingsManager]: Resetting IcfgTransformer preferences to default values
[2020-07-21 16:05:29,193 INFO  L184        SettingsManager]: ReqToTest provides no preferences, ignoring...
[2020-07-21 16:05:29,193 INFO  L181        SettingsManager]: Resetting Boogie Printer preferences to default values
[2020-07-21 16:05:29,194 INFO  L181        SettingsManager]: Resetting ChcSmtPrinter preferences to default values
[2020-07-21 16:05:29,195 INFO  L181        SettingsManager]: Resetting ReqPrinter preferences to default values
[2020-07-21 16:05:29,197 INFO  L181        SettingsManager]: Resetting Witness Printer preferences to default values
[2020-07-21 16:05:29,198 INFO  L184        SettingsManager]: Boogie PL CUP Parser provides no preferences, ignoring...
[2020-07-21 16:05:29,199 INFO  L181        SettingsManager]: Resetting CDTParser preferences to default values
[2020-07-21 16:05:29,200 INFO  L184        SettingsManager]: AutomataScriptParser provides no preferences, ignoring...
[2020-07-21 16:05:29,200 INFO  L184        SettingsManager]: ReqParser provides no preferences, ignoring...
[2020-07-21 16:05:29,200 INFO  L181        SettingsManager]: Resetting SmtParser preferences to default values
[2020-07-21 16:05:29,202 INFO  L181        SettingsManager]: Resetting Witness Parser preferences to default values
[2020-07-21 16:05:29,203 INFO  L188        SettingsManager]: Finished resetting all preferences to default values...
[2020-07-21 16:05:29,204 INFO  L101        SettingsManager]: Beginning loading settings from /storage/repos/ultimate/releaseScripts/default/UAutomizer-linux/../../../trunk/examples/settings/default/automizer/svcomp-Reach-32bit-Automizer_Default.epf
[2020-07-21 16:05:29,224 INFO  L113        SettingsManager]: Loading preferences was successful
[2020-07-21 16:05:29,225 INFO  L115        SettingsManager]: Preferences different from defaults after loading the file:
[2020-07-21 16:05:29,226 INFO  L136        SettingsManager]: Preferences of BlockEncodingV2 differ from their defaults:
[2020-07-21 16:05:29,227 INFO  L138        SettingsManager]:  * Create parallel compositions if possible=false
[2020-07-21 16:05:29,227 INFO  L138        SettingsManager]:  * Use SBE=true
[2020-07-21 16:05:29,227 INFO  L136        SettingsManager]: Preferences of CACSL2BoogieTranslator differ from their defaults:
[2020-07-21 16:05:29,227 INFO  L138        SettingsManager]:  * sizeof long=4
[2020-07-21 16:05:29,228 INFO  L138        SettingsManager]:  * Overapproximate operations on floating types=true
[2020-07-21 16:05:29,228 INFO  L138        SettingsManager]:  * sizeof POINTER=4
[2020-07-21 16:05:29,228 INFO  L138        SettingsManager]:  * Check division by zero=IGNORE
[2020-07-21 16:05:29,228 INFO  L138        SettingsManager]:  * Pointer to allocated memory at dereference=IGNORE
[2020-07-21 16:05:29,228 INFO  L138        SettingsManager]:  * If two pointers are subtracted or compared they have the same base address=IGNORE
[2020-07-21 16:05:29,229 INFO  L138        SettingsManager]:  * Check array bounds for arrays that are off heap=IGNORE
[2020-07-21 16:05:29,229 INFO  L138        SettingsManager]:  * sizeof long double=12
[2020-07-21 16:05:29,229 INFO  L138        SettingsManager]:  * Check if freed pointer was valid=false
[2020-07-21 16:05:29,229 INFO  L138        SettingsManager]:  * Use constant arrays=true
[2020-07-21 16:05:29,229 INFO  L138        SettingsManager]:  * Pointer base address is valid at dereference=IGNORE
[2020-07-21 16:05:29,230 INFO  L136        SettingsManager]: Preferences of RCFGBuilder differ from their defaults:
[2020-07-21 16:05:29,230 INFO  L138        SettingsManager]:  * Size of a code block=SequenceOfStatements
[2020-07-21 16:05:29,230 INFO  L138        SettingsManager]:  * To the following directory=./dump/
[2020-07-21 16:05:29,231 INFO  L138        SettingsManager]:  * SMT solver=External_DefaultMode
[2020-07-21 16:05:29,231 INFO  L138        SettingsManager]:  * Command for external solver=z3 SMTLIB2_COMPLIANT=true -memory:2024 -smt2 -in -t:2000
[2020-07-21 16:05:29,231 INFO  L136        SettingsManager]: Preferences of TraceAbstraction differ from their defaults:
[2020-07-21 16:05:29,231 INFO  L138        SettingsManager]:  * Compute Interpolants along a Counterexample=FPandBP
[2020-07-21 16:05:29,232 INFO  L138        SettingsManager]:  * Positions where we compute the Hoare Annotation=LoopsAndPotentialCycles
[2020-07-21 16:05:29,232 INFO  L138        SettingsManager]:  * Trace refinement strategy=CAMEL
[2020-07-21 16:05:29,232 INFO  L138        SettingsManager]:  * Command for external solver=z3 SMTLIB2_COMPLIANT=true -memory:2024 -smt2 -in
[2020-07-21 16:05:29,232 INFO  L138        SettingsManager]:  * Compute Hoare Annotation of negated interpolant automaton, abstraction and CFG=true
[2020-07-21 16:05:29,232 INFO  L138        SettingsManager]:  * Trace refinement exception blacklist=NONE
[2020-07-21 16:05:29,232 INFO  L138        SettingsManager]:  * SMT solver=External_ModelsAndUnsatCoreMode
Applying setting for plugin de.uni_freiburg.informatik.ultimate.plugins.generator.traceabstraction: Trace refinement strategy -> FIXED_PREFERENCES
Applying setting for plugin de.uni_freiburg.informatik.ultimate.plugins.generator.traceabstraction: Compute Interpolants along a Counterexample -> FPandBPonlyIfFpWasNotPerfect
Applying setting for plugin de.uni_freiburg.informatik.ultimate.plugins.generator.traceabstraction: Assert CodeBlocks -> SMT_FEATURE_HEURISTIC
Applying setting for plugin de.uni_freiburg.informatik.ultimate.plugins.generator.traceabstraction: Assert CodeBlocks Term Scoring Heuristic -> NUM_VARIABLES
Applying setting for plugin de.uni_freiburg.informatik.ultimate.plugins.generator.traceabstraction: Assert CodeBlocks Term Scoring Heuristic Partitioning Strategy -> FIXED_NUM_PARTITIONS
Applying setting for plugin de.uni_freiburg.informatik.ultimate.plugins.generator.traceabstraction: Assert CodeBlocks Term Scoring Heuristic number of partitions -> 2
[2020-07-21 16:05:29,640 INFO  L81    nceAwareModelManager]: Repository-Root is: /tmp
[2020-07-21 16:05:29,661 INFO  L258   ainManager$Toolchain]: [Toolchain 1]: Applicable parser(s) successfully (re)initialized
[2020-07-21 16:05:29,667 INFO  L214   ainManager$Toolchain]: [Toolchain 1]: Toolchain selected.
[2020-07-21 16:05:29,669 INFO  L271        PluginConnector]: Initializing CDTParser...
[2020-07-21 16:05:29,670 INFO  L275        PluginConnector]: CDTParser initialized
[2020-07-21 16:05:29,672 INFO  L429   ainManager$Toolchain]: [Toolchain 1]: Parsing single file: /storage/repos/ultimate/releaseScripts/default/UAutomizer-linux/../../../trunk/examples/svcomp/recursive-simple/id_o20.c
[2020-07-21 16:05:29,808 INFO  L220              CDTParser]: Created temporary CDT project at /storage/repos/ultimate/releaseScripts/default/UAutomizer-linux/data/d5a903962/cfd747c50998409884f14f6bab5b3c8d/FLAGb249fcc77
[2020-07-21 16:05:30,546 INFO  L306              CDTParser]: Found 1 translation units.
[2020-07-21 16:05:30,548 INFO  L160              CDTParser]: Scanning /storage/repos/ultimate/trunk/examples/svcomp/recursive-simple/id_o20.c
[2020-07-21 16:05:30,560 INFO  L349              CDTParser]: About to delete temporary CDT project at /storage/repos/ultimate/releaseScripts/default/UAutomizer-linux/data/d5a903962/cfd747c50998409884f14f6bab5b3c8d/FLAGb249fcc77
[2020-07-21 16:05:30,891 INFO  L357              CDTParser]: Successfully deleted /storage/repos/ultimate/releaseScripts/default/UAutomizer-linux/data/d5a903962/cfd747c50998409884f14f6bab5b3c8d
[2020-07-21 16:05:30,906 INFO  L296   ainManager$Toolchain]: ####################### [Toolchain 1] #######################
[2020-07-21 16:05:30,914 INFO  L131        ToolchainWalker]: Walking toolchain with 4 elements.
[2020-07-21 16:05:30,919 INFO  L113        PluginConnector]: ------------------------CACSL2BoogieTranslator----------------------------
[2020-07-21 16:05:30,920 INFO  L271        PluginConnector]: Initializing CACSL2BoogieTranslator...
[2020-07-21 16:05:30,926 INFO  L275        PluginConnector]: CACSL2BoogieTranslator initialized
[2020-07-21 16:05:30,927 INFO  L185        PluginConnector]: Executing the observer ACSLObjectContainerObserver from plugin CACSL2BoogieTranslator for "CDTParser AST 21.07 04:05:30" (1/1) ...
[2020-07-21 16:05:30,933 INFO  L205        PluginConnector]: Invalid model from CACSL2BoogieTranslator for observer de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator.ACSLObjectContainerObserver@57469803 and model type de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 21.07 04:05:30, skipping insertion in model container
[2020-07-21 16:05:30,933 INFO  L185        PluginConnector]: Executing the observer CACSL2BoogieTranslatorObserver from plugin CACSL2BoogieTranslator for "CDTParser AST 21.07 04:05:30" (1/1) ...
[2020-07-21 16:05:30,948 INFO  L145         MainTranslator]: Starting translation in SV-COMP mode 
[2020-07-21 16:05:30,979 INFO  L178         MainTranslator]: Built tables and reachable declarations
[2020-07-21 16:05:31,232 INFO  L206          PostProcessor]: Analyzing one entry point: main
[2020-07-21 16:05:31,240 INFO  L203         MainTranslator]: Completed pre-run
[2020-07-21 16:05:31,263 INFO  L206          PostProcessor]: Analyzing one entry point: main
[2020-07-21 16:05:31,287 INFO  L208         MainTranslator]: Completed translation
[2020-07-21 16:05:31,288 INFO  L202        PluginConnector]: Adding new model de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 21.07 04:05:31 WrapperNode
[2020-07-21 16:05:31,289 INFO  L132        PluginConnector]: ------------------------ END CACSL2BoogieTranslator----------------------------
[2020-07-21 16:05:31,291 INFO  L113        PluginConnector]: ------------------------Boogie Preprocessor----------------------------
[2020-07-21 16:05:31,291 INFO  L271        PluginConnector]: Initializing Boogie Preprocessor...
[2020-07-21 16:05:31,292 INFO  L275        PluginConnector]: Boogie Preprocessor initialized
[2020-07-21 16:05:31,315 INFO  L185        PluginConnector]: Executing the observer EnsureBoogieModelObserver from plugin Boogie Preprocessor for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 21.07 04:05:31" (1/1) ...
[2020-07-21 16:05:31,316 INFO  L185        PluginConnector]: Executing the observer TypeChecker from plugin Boogie Preprocessor for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 21.07 04:05:31" (1/1) ...
[2020-07-21 16:05:31,323 INFO  L185        PluginConnector]: Executing the observer ConstExpander from plugin Boogie Preprocessor for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 21.07 04:05:31" (1/1) ...
[2020-07-21 16:05:31,324 INFO  L185        PluginConnector]: Executing the observer StructExpander from plugin Boogie Preprocessor for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 21.07 04:05:31" (1/1) ...
[2020-07-21 16:05:31,330 INFO  L185        PluginConnector]: Executing the observer UnstructureCode from plugin Boogie Preprocessor for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 21.07 04:05:31" (1/1) ...
[2020-07-21 16:05:31,334 INFO  L185        PluginConnector]: Executing the observer FunctionInliner from plugin Boogie Preprocessor for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 21.07 04:05:31" (1/1) ...
[2020-07-21 16:05:31,335 INFO  L185        PluginConnector]: Executing the observer BoogieSymbolTableConstructor from plugin Boogie Preprocessor for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 21.07 04:05:31" (1/1) ...
[2020-07-21 16:05:31,338 INFO  L132        PluginConnector]: ------------------------ END Boogie Preprocessor----------------------------
[2020-07-21 16:05:31,339 INFO  L113        PluginConnector]: ------------------------RCFGBuilder----------------------------
[2020-07-21 16:05:31,340 INFO  L271        PluginConnector]: Initializing RCFGBuilder...
[2020-07-21 16:05:31,340 INFO  L275        PluginConnector]: RCFGBuilder initialized
[2020-07-21 16:05:31,342 INFO  L185        PluginConnector]: Executing the observer RCFGBuilderObserver from plugin RCFGBuilder for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 21.07 04:05:31" (1/1) ...
No working directory specified, using /storage/repos/ultimate/releaseScripts/default/UAutomizer-linux/z3
Starting monitored process 1 with z3 SMTLIB2_COMPLIANT=true -memory:2024 -smt2 -in -t:2000 (exit command is (exit), workingDir is null)
Waiting until toolchain timeout for monitored process 1 with z3 SMTLIB2_COMPLIANT=true -memory:2024 -smt2 -in -t:2000
[2020-07-21 16:05:31,567 INFO  L138     BoogieDeclarations]: Found implementation of procedure ULTIMATE.init
[2020-07-21 16:05:31,568 INFO  L138     BoogieDeclarations]: Found implementation of procedure ULTIMATE.start
[2020-07-21 16:05:31,568 INFO  L138     BoogieDeclarations]: Found implementation of procedure id
[2020-07-21 16:05:31,568 INFO  L138     BoogieDeclarations]: Found implementation of procedure main
[2020-07-21 16:05:31,568 INFO  L130     BoogieDeclarations]: Found specification of procedure __VERIFIER_nondet_uint
[2020-07-21 16:05:31,570 INFO  L130     BoogieDeclarations]: Found specification of procedure __VERIFIER_error
[2020-07-21 16:05:31,570 INFO  L130     BoogieDeclarations]: Found specification of procedure id
[2020-07-21 16:05:31,571 INFO  L130     BoogieDeclarations]: Found specification of procedure main
[2020-07-21 16:05:31,572 INFO  L130     BoogieDeclarations]: Found specification of procedure ULTIMATE.init
[2020-07-21 16:05:31,572 INFO  L130     BoogieDeclarations]: Found specification of procedure ULTIMATE.start
[2020-07-21 16:05:31,831 INFO  L290             CfgBuilder]: Using the 1 location(s) as analysis (start of procedure ULTIMATE.start)
[2020-07-21 16:05:31,831 INFO  L295             CfgBuilder]: Removed 0 assume(true) statements.
[2020-07-21 16:05:31,837 INFO  L202        PluginConnector]: Adding new model de.uni_freiburg.informatik.ultimate.plugins.generator.rcfgbuilder CFG 21.07 04:05:31 BoogieIcfgContainer
[2020-07-21 16:05:31,838 INFO  L132        PluginConnector]: ------------------------ END RCFGBuilder----------------------------
[2020-07-21 16:05:31,840 INFO  L113        PluginConnector]: ------------------------TraceAbstraction----------------------------
[2020-07-21 16:05:31,840 INFO  L271        PluginConnector]: Initializing TraceAbstraction...
[2020-07-21 16:05:31,845 INFO  L275        PluginConnector]: TraceAbstraction initialized
[2020-07-21 16:05:31,846 INFO  L185        PluginConnector]: Executing the observer TraceAbstractionObserver from plugin TraceAbstraction for "CDTParser AST 21.07 04:05:30" (1/3) ...
[2020-07-21 16:05:31,848 INFO  L205        PluginConnector]: Invalid model from TraceAbstraction for observer de.uni_freiburg.informatik.ultimate.plugins.generator.traceabstraction.TraceAbstractionObserver@13223765 and model type de.uni_freiburg.informatik.ultimate.plugins.generator.traceabstraction AST 21.07 04:05:31, skipping insertion in model container
[2020-07-21 16:05:31,848 INFO  L185        PluginConnector]: Executing the observer TraceAbstractionObserver from plugin TraceAbstraction for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 21.07 04:05:31" (2/3) ...
[2020-07-21 16:05:31,849 INFO  L205        PluginConnector]: Invalid model from TraceAbstraction for observer de.uni_freiburg.informatik.ultimate.plugins.generator.traceabstraction.TraceAbstractionObserver@13223765 and model type de.uni_freiburg.informatik.ultimate.plugins.generator.traceabstraction AST 21.07 04:05:31, skipping insertion in model container
[2020-07-21 16:05:31,849 INFO  L185        PluginConnector]: Executing the observer TraceAbstractionObserver from plugin TraceAbstraction for "de.uni_freiburg.informatik.ultimate.plugins.generator.rcfgbuilder CFG 21.07 04:05:31" (3/3) ...
[2020-07-21 16:05:31,852 INFO  L109   eAbstractionObserver]: Analyzing ICFG id_o20.c
[2020-07-21 16:05:31,868 INFO  L157   ceAbstractionStarter]: Automizer settings: Hoare:true NWA Interpolation:FPandBPonlyIfFpWasNotPerfect Determinization: PREDICATE_ABSTRACTION
[2020-07-21 16:05:31,882 INFO  L169   ceAbstractionStarter]: Appying trace abstraction to program that has 1 error locations.
[2020-07-21 16:05:31,908 INFO  L251      AbstractCegarLoop]: Starting to check reachability of 1 error locations.
[2020-07-21 16:05:31,945 INFO  L375      AbstractCegarLoop]: Interprodecural is true
[2020-07-21 16:05:31,946 INFO  L376      AbstractCegarLoop]: Hoare is true
[2020-07-21 16:05:31,946 INFO  L377      AbstractCegarLoop]: Compute interpolants for FPandBPonlyIfFpWasNotPerfect
[2020-07-21 16:05:31,947 INFO  L378      AbstractCegarLoop]: Backedges is STRAIGHT_LINE
[2020-07-21 16:05:31,947 INFO  L379      AbstractCegarLoop]: Determinization is PREDICATE_ABSTRACTION
[2020-07-21 16:05:31,947 INFO  L380      AbstractCegarLoop]: Difference is false
[2020-07-21 16:05:31,947 INFO  L381      AbstractCegarLoop]: Minimize is MINIMIZE_SEVPA
[2020-07-21 16:05:31,947 INFO  L385      AbstractCegarLoop]: ======== Iteration 0==of CEGAR loop == AllErrorsAtOnce========
[2020-07-21 16:05:31,972 INFO  L276                IsEmpty]: Start isEmpty. Operand 20 states.
[2020-07-21 16:05:31,982 INFO  L282                IsEmpty]: Finished isEmpty. Found accepting run of length 14
[2020-07-21 16:05:31,982 INFO  L414         BasicCegarLoop]: Found error trace
[2020-07-21 16:05:31,984 INFO  L422         BasicCegarLoop]: trace histogram [1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1]
[2020-07-21 16:05:31,985 INFO  L427      AbstractCegarLoop]: === Iteration 1 === [mainErr0ASSERT_VIOLATIONERROR_FUNCTION]===
[2020-07-21 16:05:31,994 INFO  L144       PredicateUnifier]: Initialized classic predicate unifier
[2020-07-21 16:05:31,995 INFO  L82        PathProgramCache]: Analyzing trace with hash -872342019, now seen corresponding path program 1 times
[2020-07-21 16:05:32,006 INFO  L163   FreeRefinementEngine]: Executing refinement strategy FIXED_PREFERENCES
[2020-07-21 16:05:32,008 INFO  L354   FreeRefinementEngine]: Using trace check IpTcStrategyModulePreferences [464280651]
[2020-07-21 16:05:32,008 INFO  L95    rtionOrderModulation]: Keeping assertion order SMT_FEATURE_HEURISTIC (partitioning type FIXED_NUM_PARTITIONS, 2 partitions)
No working directory specified, using /storage/repos/ultimate/releaseScripts/default/UAutomizer-linux/z3
Starting monitored process 2 with z3 SMTLIB2_COMPLIANT=true -memory:2024 -smt2 -in (exit command is (exit), workingDir is null)
Waiting until toolchain timeout for monitored process 2 with z3 SMTLIB2_COMPLIANT=true -memory:2024 -smt2 -in
[2020-07-21 16:05:32,107 INFO  L228   tOrderPrioritization]: Assert order SMT_FEATURE_HEURISTIC (partitioning type FIXED_NUM_PARTITIONS, 2 partitions) issued 2 check-sat command(s)
[2020-07-21 16:05:32,108 INFO  L229   tOrderPrioritization]: Conjunction of SSA is unsat
[2020-07-21 16:05:32,114 INFO  L263         TraceCheckSpWp]: Trace formula consists of 30 conjuncts, 7 conjunts are in the unsatisfiable core
[2020-07-21 16:05:32,123 INFO  L286         TraceCheckSpWp]: Computing forward predicates...
[2020-07-21 16:05:32,248 INFO  L134       CoverageAnalysis]: Checked inductivity of 0 backedges. 0 proven. 0 refuted. 0 times theorem prover too weak. 0 trivial. 0 not checked.
[2020-07-21 16:05:32,249 INFO  L324         TraceCheckSpWp]: Omiting computation of backward sequence because forward sequence was already perfect
[2020-07-21 16:05:32,251 INFO  L354   FreeRefinementEngine]: Using interpolant generator IpTcStrategyModulePreferences [464280651]
[2020-07-21 16:05:32,253 INFO  L220   FreeRefinementEngine]: Constructing automaton from 1 perfect and 0 imperfect interpolant sequences.
[2020-07-21 16:05:32,253 INFO  L233   FreeRefinementEngine]: Number of different interpolants: perfect sequences [5] imperfect sequences [] total 5
[2020-07-21 16:05:32,255 INFO  L156   tionRefinementEngine]: Using interpolant automaton builder IpAbStrategyModuleStraightlineAll [903993584]
[2020-07-21 16:05:32,266 INFO  L459      AbstractCegarLoop]: Interpolant automaton has 5 states
[2020-07-21 16:05:32,267 INFO  L143   FreeRefinementEngine]: Using predicate unifier PredicateUnifier provided by strategy FIXED_PREFERENCES
[2020-07-21 16:05:32,337 INFO  L142   InterpolantAutomaton]: Constructing interpolant automaton starting with 5 interpolants.
[2020-07-21 16:05:32,343 INFO  L144   InterpolantAutomaton]: CoverageRelationStatistics Valid=7, Invalid=13, Unknown=0, NotChecked=0, Total=20
[2020-07-21 16:05:32,353 INFO  L87              Difference]: Start difference. First operand 20 states. Second operand 5 states.
[2020-07-21 16:05:32,451 INFO  L144             Difference]: Subtrahend was deterministic. Have not used determinization.
[2020-07-21 16:05:32,452 INFO  L93              Difference]: Finished difference Result 32 states and 35 transitions.
[2020-07-21 16:05:32,453 INFO  L141   InterpolantAutomaton]: Switched to read-only mode: deterministic interpolant automaton has 5 states. 
[2020-07-21 16:05:32,455 INFO  L78                 Accepts]: Start accepts. Automaton has 5 states. Word has length 13
[2020-07-21 16:05:32,457 INFO  L84                 Accepts]: Finished accepts. some prefix is accepted.
[2020-07-21 16:05:32,472 INFO  L225             Difference]: With dead ends: 32
[2020-07-21 16:05:32,473 INFO  L226             Difference]: Without dead ends: 18
[2020-07-21 16:05:32,479 INFO  L675         BasicCegarLoop]: 0 DeclaredPredicates, 12 GetRequests, 9 SyntacticMatches, 0 SemanticMatches, 3 ConstructedPredicates, 0 IntricatePredicates, 0 DeprecatedPredicates, 0 ImplicationChecksByTransitivity, 0.0s TimeCoverageRelationStatistics Valid=7, Invalid=13, Unknown=0, NotChecked=0, Total=20
[2020-07-21 16:05:32,508 INFO  L82        GeneralOperation]: Start minimizeSevpa. Operand 18 states.
[2020-07-21 16:05:32,542 INFO  L88        GeneralOperation]: Finished minimizeSevpa. Reduced states from 18 to 18.
[2020-07-21 16:05:32,544 INFO  L82        GeneralOperation]: Start removeUnreachable. Operand 18 states.
[2020-07-21 16:05:32,546 INFO  L88        GeneralOperation]: Finished removeUnreachable. Reduced from 18 states to 18 states and 19 transitions.
[2020-07-21 16:05:32,549 INFO  L78                 Accepts]: Start accepts. Automaton has 18 states and 19 transitions. Word has length 13
[2020-07-21 16:05:32,550 INFO  L84                 Accepts]: Finished accepts. word is rejected.
[2020-07-21 16:05:32,550 INFO  L479      AbstractCegarLoop]: Abstraction has 18 states and 19 transitions.
[2020-07-21 16:05:32,550 INFO  L480      AbstractCegarLoop]: Interpolant automaton has 5 states.
[2020-07-21 16:05:32,551 INFO  L276                IsEmpty]: Start isEmpty. Operand 18 states and 19 transitions.
[2020-07-21 16:05:32,554 INFO  L282                IsEmpty]: Finished isEmpty. Found accepting run of length 20
[2020-07-21 16:05:32,554 INFO  L414         BasicCegarLoop]: Found error trace
[2020-07-21 16:05:32,554 INFO  L422         BasicCegarLoop]: trace histogram [2, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1]
[2020-07-21 16:05:32,771 WARN  L516      AbstractCegarLoop]: Destroyed unattended storables created during the last iteration: 2 z3 SMTLIB2_COMPLIANT=true -memory:2024 -smt2 -in
[2020-07-21 16:05:32,771 INFO  L427      AbstractCegarLoop]: === Iteration 2 === [mainErr0ASSERT_VIOLATIONERROR_FUNCTION]===
[2020-07-21 16:05:32,772 INFO  L144       PredicateUnifier]: Initialized classic predicate unifier
[2020-07-21 16:05:32,772 INFO  L82        PathProgramCache]: Analyzing trace with hash -953570577, now seen corresponding path program 1 times
[2020-07-21 16:05:32,773 INFO  L163   FreeRefinementEngine]: Executing refinement strategy FIXED_PREFERENCES
[2020-07-21 16:05:32,773 INFO  L354   FreeRefinementEngine]: Using trace check IpTcStrategyModulePreferences [2042519469]
[2020-07-21 16:05:32,781 INFO  L95    rtionOrderModulation]: Keeping assertion order SMT_FEATURE_HEURISTIC (partitioning type FIXED_NUM_PARTITIONS, 2 partitions)
No working directory specified, using /storage/repos/ultimate/releaseScripts/default/UAutomizer-linux/z3
Starting monitored process 3 with z3 SMTLIB2_COMPLIANT=true -memory:2024 -smt2 -in (exit command is (exit), workingDir is null)
Waiting until toolchain timeout for monitored process 3 with z3 SMTLIB2_COMPLIANT=true -memory:2024 -smt2 -in
[2020-07-21 16:05:32,870 INFO  L228   tOrderPrioritization]: Assert order SMT_FEATURE_HEURISTIC (partitioning type FIXED_NUM_PARTITIONS, 2 partitions) issued 2 check-sat command(s)
[2020-07-21 16:05:32,871 INFO  L229   tOrderPrioritization]: Conjunction of SSA is unsat
[2020-07-21 16:05:32,873 INFO  L263         TraceCheckSpWp]: Trace formula consists of 42 conjuncts, 12 conjunts are in the unsatisfiable core
[2020-07-21 16:05:32,876 INFO  L286         TraceCheckSpWp]: Computing forward predicates...
[2020-07-21 16:05:32,952 INFO  L134       CoverageAnalysis]: Checked inductivity of 4 backedges. 0 proven. 2 refuted. 0 times theorem prover too weak. 2 trivial. 0 not checked.
[2020-07-21 16:05:32,953 INFO  L328         TraceCheckSpWp]: Computing backward predicates...
[2020-07-21 16:05:33,345 INFO  L134       CoverageAnalysis]: Checked inductivity of 4 backedges. 0 proven. 2 refuted. 0 times theorem prover too weak. 2 trivial. 0 not checked.
[2020-07-21 16:05:33,347 INFO  L354   FreeRefinementEngine]: Using interpolant generator IpTcStrategyModulePreferences [2042519469]
[2020-07-21 16:05:33,347 INFO  L220   FreeRefinementEngine]: Constructing automaton from 0 perfect and 2 imperfect interpolant sequences.
[2020-07-21 16:05:33,348 INFO  L233   FreeRefinementEngine]: Number of different interpolants: perfect sequences [] imperfect sequences [7, 7] total 12
[2020-07-21 16:05:33,348 INFO  L156   tionRefinementEngine]: Using interpolant automaton builder IpAbStrategyModuleStraightlineAll [1601259148]
[2020-07-21 16:05:33,351 INFO  L459      AbstractCegarLoop]: Interpolant automaton has 12 states
[2020-07-21 16:05:33,352 INFO  L143   FreeRefinementEngine]: Using predicate unifier PredicateUnifier provided by strategy FIXED_PREFERENCES
[2020-07-21 16:05:33,353 INFO  L142   InterpolantAutomaton]: Constructing interpolant automaton starting with 12 interpolants.
[2020-07-21 16:05:33,354 INFO  L144   InterpolantAutomaton]: CoverageRelationStatistics Valid=28, Invalid=104, Unknown=0, NotChecked=0, Total=132
[2020-07-21 16:05:33,354 INFO  L87              Difference]: Start difference. First operand 18 states and 19 transitions. Second operand 12 states.
[2020-07-21 16:05:33,441 INFO  L144             Difference]: Subtrahend was deterministic. Have not used determinization.
[2020-07-21 16:05:33,441 INFO  L93              Difference]: Finished difference Result 30 states and 32 transitions.
[2020-07-21 16:05:33,442 INFO  L141   InterpolantAutomaton]: Switched to read-only mode: deterministic interpolant automaton has 11 states. 
[2020-07-21 16:05:33,443 INFO  L78                 Accepts]: Start accepts. Automaton has 12 states. Word has length 19
[2020-07-21 16:05:33,443 INFO  L84                 Accepts]: Finished accepts. some prefix is accepted.
[2020-07-21 16:05:33,445 INFO  L225             Difference]: With dead ends: 30
[2020-07-21 16:05:33,445 INFO  L226             Difference]: Without dead ends: 24
[2020-07-21 16:05:33,447 INFO  L675         BasicCegarLoop]: 0 DeclaredPredicates, 37 GetRequests, 27 SyntacticMatches, 0 SemanticMatches, 10 ConstructedPredicates, 0 IntricatePredicates, 0 DeprecatedPredicates, 9 ImplicationChecksByTransitivity, 0.2s TimeCoverageRelationStatistics Valid=28, Invalid=104, Unknown=0, NotChecked=0, Total=132
[2020-07-21 16:05:33,449 INFO  L82        GeneralOperation]: Start minimizeSevpa. Operand 24 states.
[2020-07-21 16:05:33,456 INFO  L88        GeneralOperation]: Finished minimizeSevpa. Reduced states from 24 to 24.
[2020-07-21 16:05:33,457 INFO  L82        GeneralOperation]: Start removeUnreachable. Operand 24 states.
[2020-07-21 16:05:33,458 INFO  L88        GeneralOperation]: Finished removeUnreachable. Reduced from 24 states to 24 states and 25 transitions.
[2020-07-21 16:05:33,459 INFO  L78                 Accepts]: Start accepts. Automaton has 24 states and 25 transitions. Word has length 19
[2020-07-21 16:05:33,459 INFO  L84                 Accepts]: Finished accepts. word is rejected.
[2020-07-21 16:05:33,459 INFO  L479      AbstractCegarLoop]: Abstraction has 24 states and 25 transitions.
[2020-07-21 16:05:33,460 INFO  L480      AbstractCegarLoop]: Interpolant automaton has 12 states.
[2020-07-21 16:05:33,460 INFO  L276                IsEmpty]: Start isEmpty. Operand 24 states and 25 transitions.
[2020-07-21 16:05:33,461 INFO  L282                IsEmpty]: Finished isEmpty. Found accepting run of length 32
[2020-07-21 16:05:33,462 INFO  L414         BasicCegarLoop]: Found error trace
[2020-07-21 16:05:33,462 INFO  L422         BasicCegarLoop]: trace histogram [4, 4, 3, 3, 3, 3, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1]
[2020-07-21 16:05:33,676 WARN  L516      AbstractCegarLoop]: Destroyed unattended storables created during the last iteration: 3 z3 SMTLIB2_COMPLIANT=true -memory:2024 -smt2 -in
[2020-07-21 16:05:33,677 INFO  L427      AbstractCegarLoop]: === Iteration 3 === [mainErr0ASSERT_VIOLATIONERROR_FUNCTION]===
[2020-07-21 16:05:33,678 INFO  L144       PredicateUnifier]: Initialized classic predicate unifier
[2020-07-21 16:05:33,679 INFO  L82        PathProgramCache]: Analyzing trace with hash 1198310127, now seen corresponding path program 2 times
[2020-07-21 16:05:33,679 INFO  L163   FreeRefinementEngine]: Executing refinement strategy FIXED_PREFERENCES
[2020-07-21 16:05:33,680 INFO  L354   FreeRefinementEngine]: Using trace check IpTcStrategyModulePreferences [2037565895]
[2020-07-21 16:05:33,681 INFO  L95    rtionOrderModulation]: Keeping assertion order SMT_FEATURE_HEURISTIC (partitioning type FIXED_NUM_PARTITIONS, 2 partitions)
No working directory specified, using /storage/repos/ultimate/releaseScripts/default/UAutomizer-linux/z3
Starting monitored process 4 with z3 SMTLIB2_COMPLIANT=true -memory:2024 -smt2 -in (exit command is (exit), workingDir is null)
Waiting until toolchain timeout for monitored process 4 with z3 SMTLIB2_COMPLIANT=true -memory:2024 -smt2 -in
[2020-07-21 16:05:33,735 INFO  L228   tOrderPrioritization]: Assert order SMT_FEATURE_HEURISTIC (partitioning type FIXED_NUM_PARTITIONS, 2 partitions) issued 2 check-sat command(s)
[2020-07-21 16:05:33,736 INFO  L229   tOrderPrioritization]: Conjunction of SSA is unsat
[2020-07-21 16:05:33,739 INFO  L263         TraceCheckSpWp]: Trace formula consists of 66 conjuncts, 19 conjunts are in the unsatisfiable core
[2020-07-21 16:05:33,746 INFO  L286         TraceCheckSpWp]: Computing forward predicates...
[2020-07-21 16:05:34,004 INFO  L134       CoverageAnalysis]: Checked inductivity of 30 backedges. 0 proven. 15 refuted. 0 times theorem prover too weak. 15 trivial. 0 not checked.
[2020-07-21 16:05:34,005 INFO  L328         TraceCheckSpWp]: Computing backward predicates...
[2020-07-21 16:05:34,738 INFO  L134       CoverageAnalysis]: Checked inductivity of 30 backedges. 0 proven. 15 refuted. 0 times theorem prover too weak. 15 trivial. 0 not checked.
[2020-07-21 16:05:34,739 INFO  L354   FreeRefinementEngine]: Using interpolant generator IpTcStrategyModulePreferences [2037565895]
[2020-07-21 16:05:34,739 INFO  L220   FreeRefinementEngine]: Constructing automaton from 0 perfect and 2 imperfect interpolant sequences.
[2020-07-21 16:05:34,740 INFO  L233   FreeRefinementEngine]: Number of different interpolants: perfect sequences [] imperfect sequences [11, 11] total 20
[2020-07-21 16:05:34,740 INFO  L156   tionRefinementEngine]: Using interpolant automaton builder IpAbStrategyModuleStraightlineAll [433157733]
[2020-07-21 16:05:34,742 INFO  L459      AbstractCegarLoop]: Interpolant automaton has 20 states
[2020-07-21 16:05:34,742 INFO  L143   FreeRefinementEngine]: Using predicate unifier PredicateUnifier provided by strategy FIXED_PREFERENCES
[2020-07-21 16:05:34,743 INFO  L142   InterpolantAutomaton]: Constructing interpolant automaton starting with 20 interpolants.
[2020-07-21 16:05:34,744 INFO  L144   InterpolantAutomaton]: CoverageRelationStatistics Valid=64, Invalid=316, Unknown=0, NotChecked=0, Total=380
[2020-07-21 16:05:34,744 INFO  L87              Difference]: Start difference. First operand 24 states and 25 transitions. Second operand 20 states.
[2020-07-21 16:05:37,580 WARN  L193               SmtUtils]: Spent 2.09 s on a formula simplification that was a NOOP. DAG size: 11
[2020-07-21 16:05:37,623 INFO  L144             Difference]: Subtrahend was deterministic. Have not used determinization.
[2020-07-21 16:05:37,624 INFO  L93              Difference]: Finished difference Result 42 states and 46 transitions.
[2020-07-21 16:05:37,624 INFO  L141   InterpolantAutomaton]: Switched to read-only mode: deterministic interpolant automaton has 19 states. 
[2020-07-21 16:05:37,625 INFO  L78                 Accepts]: Start accepts. Automaton has 20 states. Word has length 31
[2020-07-21 16:05:37,625 INFO  L84                 Accepts]: Finished accepts. some prefix is accepted.
[2020-07-21 16:05:37,627 INFO  L225             Difference]: With dead ends: 42
[2020-07-21 16:05:37,627 INFO  L226             Difference]: Without dead ends: 36
[2020-07-21 16:05:37,631 INFO  L675         BasicCegarLoop]: 0 DeclaredPredicates, 65 GetRequests, 43 SyntacticMatches, 0 SemanticMatches, 22 ConstructedPredicates, 0 IntricatePredicates, 0 DeprecatedPredicates, 33 ImplicationChecksByTransitivity, 3.2s TimeCoverageRelationStatistics Valid=98, Invalid=454, Unknown=0, NotChecked=0, Total=552
[2020-07-21 16:05:37,632 INFO  L82        GeneralOperation]: Start minimizeSevpa. Operand 36 states.
[2020-07-21 16:05:37,640 INFO  L88        GeneralOperation]: Finished minimizeSevpa. Reduced states from 36 to 36.
[2020-07-21 16:05:37,641 INFO  L82        GeneralOperation]: Start removeUnreachable. Operand 36 states.
[2020-07-21 16:05:37,642 INFO  L88        GeneralOperation]: Finished removeUnreachable. Reduced from 36 states to 36 states and 37 transitions.
[2020-07-21 16:05:37,643 INFO  L78                 Accepts]: Start accepts. Automaton has 36 states and 37 transitions. Word has length 31
[2020-07-21 16:05:37,643 INFO  L84                 Accepts]: Finished accepts. word is rejected.
[2020-07-21 16:05:37,643 INFO  L479      AbstractCegarLoop]: Abstraction has 36 states and 37 transitions.
[2020-07-21 16:05:37,643 INFO  L480      AbstractCegarLoop]: Interpolant automaton has 20 states.
[2020-07-21 16:05:37,644 INFO  L276                IsEmpty]: Start isEmpty. Operand 36 states and 37 transitions.
[2020-07-21 16:05:37,646 INFO  L282                IsEmpty]: Finished isEmpty. Found accepting run of length 56
[2020-07-21 16:05:37,646 INFO  L414         BasicCegarLoop]: Found error trace
[2020-07-21 16:05:37,646 INFO  L422         BasicCegarLoop]: trace histogram [8, 8, 7, 7, 7, 7, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1]
[2020-07-21 16:05:37,862 WARN  L516      AbstractCegarLoop]: Destroyed unattended storables created during the last iteration: 4 z3 SMTLIB2_COMPLIANT=true -memory:2024 -smt2 -in
[2020-07-21 16:05:37,863 INFO  L427      AbstractCegarLoop]: === Iteration 4 === [mainErr0ASSERT_VIOLATIONERROR_FUNCTION]===
[2020-07-21 16:05:37,863 INFO  L144       PredicateUnifier]: Initialized classic predicate unifier
[2020-07-21 16:05:37,864 INFO  L82        PathProgramCache]: Analyzing trace with hash 1532150511, now seen corresponding path program 3 times
[2020-07-21 16:05:37,865 INFO  L163   FreeRefinementEngine]: Executing refinement strategy FIXED_PREFERENCES
[2020-07-21 16:05:37,865 INFO  L354   FreeRefinementEngine]: Using trace check IpTcStrategyModulePreferences [2052393749]
[2020-07-21 16:05:37,866 INFO  L95    rtionOrderModulation]: Keeping assertion order SMT_FEATURE_HEURISTIC (partitioning type FIXED_NUM_PARTITIONS, 2 partitions)
No working directory specified, using /storage/repos/ultimate/releaseScripts/default/UAutomizer-linux/z3
Starting monitored process 5 with z3 SMTLIB2_COMPLIANT=true -memory:2024 -smt2 -in (exit command is (exit), workingDir is null)
Waiting until toolchain timeout for monitored process 5 with z3 SMTLIB2_COMPLIANT=true -memory:2024 -smt2 -in
[2020-07-21 16:05:37,923 INFO  L228   tOrderPrioritization]: Assert order SMT_FEATURE_HEURISTIC (partitioning type FIXED_NUM_PARTITIONS, 2 partitions) issued 2 check-sat command(s)
[2020-07-21 16:05:37,924 INFO  L229   tOrderPrioritization]: Conjunction of SSA is unsat
[2020-07-21 16:05:37,926 INFO  L263         TraceCheckSpWp]: Trace formula consists of 114 conjuncts, 35 conjunts are in the unsatisfiable core
[2020-07-21 16:05:37,932 INFO  L286         TraceCheckSpWp]: Computing forward predicates...
[2020-07-21 16:05:38,263 INFO  L134       CoverageAnalysis]: Checked inductivity of 154 backedges. 0 proven. 77 refuted. 0 times theorem prover too weak. 77 trivial. 0 not checked.
[2020-07-21 16:05:38,265 INFO  L328         TraceCheckSpWp]: Computing backward predicates...
[2020-07-21 16:05:50,740 INFO  L134       CoverageAnalysis]: Checked inductivity of 154 backedges. 0 proven. 72 refuted. 5 times theorem prover too weak. 77 trivial. 0 not checked.
[2020-07-21 16:05:50,741 INFO  L354   FreeRefinementEngine]: Using interpolant generator IpTcStrategyModulePreferences [2052393749]
[2020-07-21 16:05:50,741 INFO  L220   FreeRefinementEngine]: Constructing automaton from 0 perfect and 2 imperfect interpolant sequences.
[2020-07-21 16:05:50,742 INFO  L233   FreeRefinementEngine]: Number of different interpolants: perfect sequences [] imperfect sequences [19, 19] total 36
[2020-07-21 16:05:50,742 INFO  L156   tionRefinementEngine]: Using interpolant automaton builder IpAbStrategyModuleStraightlineAll [1067445003]
[2020-07-21 16:05:50,743 INFO  L459      AbstractCegarLoop]: Interpolant automaton has 36 states
[2020-07-21 16:05:50,743 INFO  L143   FreeRefinementEngine]: Using predicate unifier PredicateUnifier provided by strategy FIXED_PREFERENCES
[2020-07-21 16:05:50,744 INFO  L142   InterpolantAutomaton]: Constructing interpolant automaton starting with 36 interpolants.
[2020-07-21 16:05:50,744 INFO  L144   InterpolantAutomaton]: CoverageRelationStatistics Valid=184, Invalid=1071, Unknown=5, NotChecked=0, Total=1260
[2020-07-21 16:05:50,745 INFO  L87              Difference]: Start difference. First operand 36 states and 37 transitions. Second operand 36 states.
[2020-07-21 16:05:55,647 WARN  L193               SmtUtils]: Spent 4.27 s on a formula simplification. DAG size of input: 38 DAG size of output: 13
[2020-07-21 16:05:56,199 WARN  L193               SmtUtils]: Spent 131.00 ms on a formula simplification. DAG size of input: 36 DAG size of output: 11
[2020-07-21 16:06:01,424 WARN  L193               SmtUtils]: Spent 2.16 s on a formula simplification. DAG size of input: 28 DAG size of output: 13
[2020-07-21 16:06:04,262 WARN  L193               SmtUtils]: Spent 2.15 s on a formula simplification. DAG size of input: 23 DAG size of output: 13
[2020-07-21 16:06:15,796 WARN  L193               SmtUtils]: Spent 2.10 s on a formula simplification that was a NOOP. DAG size: 13
[2020-07-21 16:06:18,021 INFO  L144             Difference]: Subtrahend was deterministic. Have not used determinization.
[2020-07-21 16:06:18,021 INFO  L93              Difference]: Finished difference Result 66 states and 74 transitions.
[2020-07-21 16:06:18,023 INFO  L141   InterpolantAutomaton]: Switched to read-only mode: deterministic interpolant automaton has 35 states. 
[2020-07-21 16:06:18,024 INFO  L78                 Accepts]: Start accepts. Automaton has 36 states. Word has length 55
[2020-07-21 16:06:18,026 INFO  L84                 Accepts]: Finished accepts. some prefix is accepted.
[2020-07-21 16:06:18,030 INFO  L225             Difference]: With dead ends: 66
[2020-07-21 16:06:18,030 INFO  L226             Difference]: Without dead ends: 60
[2020-07-21 16:06:18,033 INFO  L675         BasicCegarLoop]: 0 DeclaredPredicates, 121 GetRequests, 75 SyntacticMatches, 0 SemanticMatches, 46 ConstructedPredicates, 0 IntricatePredicates, 0 DeprecatedPredicates, 154 ImplicationChecksByTransitivity, 38.5s TimeCoverageRelationStatistics Valid=380, Invalid=1867, Unknown=9, NotChecked=0, Total=2256
[2020-07-21 16:06:18,035 INFO  L82        GeneralOperation]: Start minimizeSevpa. Operand 60 states.
[2020-07-21 16:06:18,046 INFO  L88        GeneralOperation]: Finished minimizeSevpa. Reduced states from 60 to 60.
[2020-07-21 16:06:18,047 INFO  L82        GeneralOperation]: Start removeUnreachable. Operand 60 states.
[2020-07-21 16:06:18,049 INFO  L88        GeneralOperation]: Finished removeUnreachable. Reduced from 60 states to 60 states and 61 transitions.
[2020-07-21 16:06:18,050 INFO  L78                 Accepts]: Start accepts. Automaton has 60 states and 61 transitions. Word has length 55
[2020-07-21 16:06:18,050 INFO  L84                 Accepts]: Finished accepts. word is rejected.
[2020-07-21 16:06:18,051 INFO  L479      AbstractCegarLoop]: Abstraction has 60 states and 61 transitions.
[2020-07-21 16:06:18,051 INFO  L480      AbstractCegarLoop]: Interpolant automaton has 36 states.
[2020-07-21 16:06:18,051 INFO  L276                IsEmpty]: Start isEmpty. Operand 60 states and 61 transitions.
[2020-07-21 16:06:18,055 INFO  L282                IsEmpty]: Finished isEmpty. Found accepting run of length 104
[2020-07-21 16:06:18,056 INFO  L414         BasicCegarLoop]: Found error trace
[2020-07-21 16:06:18,056 INFO  L422         BasicCegarLoop]: trace histogram [16, 16, 15, 15, 15, 15, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1]
[2020-07-21 16:06:18,265 WARN  L516      AbstractCegarLoop]: Destroyed unattended storables created during the last iteration: 5 z3 SMTLIB2_COMPLIANT=true -memory:2024 -smt2 -in
[2020-07-21 16:06:18,266 INFO  L427      AbstractCegarLoop]: === Iteration 5 === [mainErr0ASSERT_VIOLATIONERROR_FUNCTION]===
[2020-07-21 16:06:18,266 INFO  L144       PredicateUnifier]: Initialized classic predicate unifier
[2020-07-21 16:06:18,267 INFO  L82        PathProgramCache]: Analyzing trace with hash 1083048687, now seen corresponding path program 4 times
[2020-07-21 16:06:18,268 INFO  L163   FreeRefinementEngine]: Executing refinement strategy FIXED_PREFERENCES
[2020-07-21 16:06:18,269 INFO  L354   FreeRefinementEngine]: Using trace check IpTcStrategyModulePreferences [443505469]
[2020-07-21 16:06:18,269 INFO  L95    rtionOrderModulation]: Keeping assertion order SMT_FEATURE_HEURISTIC (partitioning type FIXED_NUM_PARTITIONS, 2 partitions)
No working directory specified, using /storage/repos/ultimate/releaseScripts/default/UAutomizer-linux/z3
Starting monitored process 6 with z3 SMTLIB2_COMPLIANT=true -memory:2024 -smt2 -in (exit command is (exit), workingDir is null)
Waiting until toolchain timeout for monitored process 6 with z3 SMTLIB2_COMPLIANT=true -memory:2024 -smt2 -in
[2020-07-21 16:06:18,380 INFO  L228   tOrderPrioritization]: Assert order SMT_FEATURE_HEURISTIC (partitioning type FIXED_NUM_PARTITIONS, 2 partitions) issued 2 check-sat command(s)
[2020-07-21 16:06:18,381 INFO  L229   tOrderPrioritization]: Conjunction of SSA is unsat
[2020-07-21 16:06:18,385 INFO  L263         TraceCheckSpWp]: Trace formula consists of 210 conjuncts, 67 conjunts are in the unsatisfiable core
[2020-07-21 16:06:18,408 INFO  L286         TraceCheckSpWp]: Computing forward predicates...
[2020-07-21 16:06:19,333 INFO  L134       CoverageAnalysis]: Checked inductivity of 690 backedges. 0 proven. 345 refuted. 0 times theorem prover too weak. 345 trivial. 0 not checked.
[2020-07-21 16:06:19,334 INFO  L328         TraceCheckSpWp]: Computing backward predicates...
[2020-07-21 16:06:45,022 INFO  L134       CoverageAnalysis]: Checked inductivity of 690 backedges. 0 proven. 343 refuted. 2 times theorem prover too weak. 345 trivial. 0 not checked.
[2020-07-21 16:06:45,023 INFO  L354   FreeRefinementEngine]: Using interpolant generator IpTcStrategyModulePreferences [443505469]
[2020-07-21 16:06:45,023 INFO  L220   FreeRefinementEngine]: Constructing automaton from 0 perfect and 2 imperfect interpolant sequences.
[2020-07-21 16:06:45,023 INFO  L233   FreeRefinementEngine]: Number of different interpolants: perfect sequences [] imperfect sequences [35, 35] total 68
[2020-07-21 16:06:45,024 INFO  L156   tionRefinementEngine]: Using interpolant automaton builder IpAbStrategyModuleStraightlineAll [652764826]
[2020-07-21 16:06:45,025 INFO  L459      AbstractCegarLoop]: Interpolant automaton has 68 states
[2020-07-21 16:06:45,025 INFO  L143   FreeRefinementEngine]: Using predicate unifier PredicateUnifier provided by strategy FIXED_PREFERENCES
[2020-07-21 16:06:45,026 INFO  L142   InterpolantAutomaton]: Constructing interpolant automaton starting with 68 interpolants.
[2020-07-21 16:06:45,030 INFO  L144   InterpolantAutomaton]: CoverageRelationStatistics Valid=495, Invalid=4052, Unknown=9, NotChecked=0, Total=4556
[2020-07-21 16:06:45,030 INFO  L87              Difference]: Start difference. First operand 60 states and 61 transitions. Second operand 68 states.
[2020-07-21 16:06:49,480 WARN  L193               SmtUtils]: Spent 2.12 s on a formula simplification. DAG size of input: 18 DAG size of output: 13
[2020-07-21 16:06:52,038 WARN  L193               SmtUtils]: Spent 2.09 s on a formula simplification that was a NOOP. DAG size: 13
[2020-07-21 16:06:54,344 INFO  L144             Difference]: Subtrahend was deterministic. Have not used determinization.
[2020-07-21 16:06:54,345 INFO  L93              Difference]: Finished difference Result 81 states and 86 transitions.
[2020-07-21 16:06:54,347 INFO  L141   InterpolantAutomaton]: Switched to read-only mode: deterministic interpolant automaton has 45 states. 
[2020-07-21 16:06:54,347 INFO  L78                 Accepts]: Start accepts. Automaton has 68 states. Word has length 103
[2020-07-21 16:06:54,349 INFO  L84                 Accepts]: Finished accepts. some prefix is accepted.
[2020-07-21 16:06:54,351 INFO  L225             Difference]: With dead ends: 81
[2020-07-21 16:06:54,352 INFO  L226             Difference]: Without dead ends: 75
[2020-07-21 16:06:54,355 INFO  L675         BasicCegarLoop]: 0 DeclaredPredicates, 211 GetRequests, 139 SyntacticMatches, 0 SemanticMatches, 72 ConstructedPredicates, 0 IntricatePredicates, 0 DeprecatedPredicates, 523 ImplicationChecksByTransitivity, 31.9s TimeCoverageRelationStatistics Valid=624, Invalid=4768, Unknown=10, NotChecked=0, Total=5402
[2020-07-21 16:06:54,356 INFO  L82        GeneralOperation]: Start minimizeSevpa. Operand 75 states.
[2020-07-21 16:06:54,368 INFO  L88        GeneralOperation]: Finished minimizeSevpa. Reduced states from 75 to 75.
[2020-07-21 16:06:54,368 INFO  L82        GeneralOperation]: Start removeUnreachable. Operand 75 states.
[2020-07-21 16:06:54,371 INFO  L88        GeneralOperation]: Finished removeUnreachable. Reduced from 75 states to 75 states and 76 transitions.
[2020-07-21 16:06:54,371 INFO  L78                 Accepts]: Start accepts. Automaton has 75 states and 76 transitions. Word has length 103
[2020-07-21 16:06:54,372 INFO  L84                 Accepts]: Finished accepts. word is rejected.
[2020-07-21 16:06:54,373 INFO  L479      AbstractCegarLoop]: Abstraction has 75 states and 76 transitions.
[2020-07-21 16:06:54,373 INFO  L480      AbstractCegarLoop]: Interpolant automaton has 68 states.
[2020-07-21 16:06:54,373 INFO  L276                IsEmpty]: Start isEmpty. Operand 75 states and 76 transitions.
[2020-07-21 16:06:54,376 INFO  L282                IsEmpty]: Finished isEmpty. Found accepting run of length 134
[2020-07-21 16:06:54,376 INFO  L414         BasicCegarLoop]: Found error trace
[2020-07-21 16:06:54,377 INFO  L422         BasicCegarLoop]: trace histogram [21, 21, 20, 20, 20, 20, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1]
[2020-07-21 16:06:54,585 WARN  L516      AbstractCegarLoop]: Destroyed unattended storables created during the last iteration: 6 z3 SMTLIB2_COMPLIANT=true -memory:2024 -smt2 -in
[2020-07-21 16:06:54,586 INFO  L427      AbstractCegarLoop]: === Iteration 6 === [mainErr0ASSERT_VIOLATIONERROR_FUNCTION]===
[2020-07-21 16:06:54,586 INFO  L144       PredicateUnifier]: Initialized classic predicate unifier
[2020-07-21 16:06:54,587 INFO  L82        PathProgramCache]: Analyzing trace with hash -799288067, now seen corresponding path program 5 times
[2020-07-21 16:06:54,588 INFO  L163   FreeRefinementEngine]: Executing refinement strategy FIXED_PREFERENCES
[2020-07-21 16:06:54,588 INFO  L354   FreeRefinementEngine]: Using trace check IpTcStrategyModulePreferences [355374769]
[2020-07-21 16:06:54,589 INFO  L95    rtionOrderModulation]: Keeping assertion order SMT_FEATURE_HEURISTIC (partitioning type FIXED_NUM_PARTITIONS, 2 partitions)
No working directory specified, using /storage/repos/ultimate/releaseScripts/default/UAutomizer-linux/z3
Starting monitored process 7 with z3 SMTLIB2_COMPLIANT=true -memory:2024 -smt2 -in (exit command is (exit), workingDir is null)
Waiting until toolchain timeout for monitored process 7 with z3 SMTLIB2_COMPLIANT=true -memory:2024 -smt2 -in
[2020-07-21 16:06:55,469 INFO  L228   tOrderPrioritization]: Assert order SMT_FEATURE_HEURISTIC (partitioning type FIXED_NUM_PARTITIONS, 2 partitions) issued 2 check-sat command(s)
[2020-07-21 16:06:55,470 INFO  L229   tOrderPrioritization]: Conjunction of SSA is sat
[2020-07-21 16:06:55,470 INFO  L221             TraceCheck]: Trace is feasible, we will do another trace check, this time with branch encoders.
[2020-07-21 16:06:55,529 INFO  L136    AnnotateAndAsserter]: Conjunction of SSA is sat
[2020-07-21 16:06:55,530 INFO  L221             TraceCheck]: Trace is feasible, we will do another trace check, this time with branch encoders.
[2020-07-21 16:06:55,587 INFO  L174   FreeRefinementEngine]: Strategy FIXED_PREFERENCES found a feasible trace
[2020-07-21 16:06:55,588 INFO  L520         BasicCegarLoop]: Counterexample might be feasible
[2020-07-21 16:06:55,798 WARN  L516      AbstractCegarLoop]: Destroyed unattended storables created during the last iteration: 7 z3 SMTLIB2_COMPLIANT=true -memory:2024 -smt2 -in
[2020-07-21 16:06:55,872 INFO  L202        PluginConnector]: Adding new model de.uni_freiburg.informatik.ultimate.plugins.generator.traceabstraction CFG 21.07 04:06:55 BoogieIcfgContainer
[2020-07-21 16:06:55,873 INFO  L132        PluginConnector]: ------------------------ END TraceAbstraction----------------------------
[2020-07-21 16:06:55,876 INFO  L168              Benchmark]: Toolchain (without parser) took 84967.29 ms. Allocated memory was 135.8 MB in the beginning and 313.5 MB in the end (delta: 177.7 MB). Free memory was 100.6 MB in the beginning and 94.8 MB in the end (delta: 5.8 MB). Peak memory consumption was 183.6 MB. Max. memory is 7.1 GB.
[2020-07-21 16:06:55,877 INFO  L168              Benchmark]: CDTParser took 0.40 ms. Allocated memory is still 135.8 MB. Free memory was 118.8 MB in the beginning and 118.6 MB in the end (delta: 210.1 kB). Peak memory consumption was 210.1 kB. Max. memory is 7.1 GB.
[2020-07-21 16:06:55,878 INFO  L168              Benchmark]: CACSL2BoogieTranslator took 370.79 ms. Allocated memory is still 135.8 MB. Free memory was 100.1 MB in the beginning and 91.0 MB in the end (delta: 9.1 MB). Peak memory consumption was 9.1 MB. Max. memory is 7.1 GB.
[2020-07-21 16:06:55,879 INFO  L168              Benchmark]: Boogie Preprocessor took 47.35 ms. Allocated memory is still 135.8 MB. Free memory was 91.0 MB in the beginning and 89.6 MB in the end (delta: 1.4 MB). Peak memory consumption was 1.4 MB. Max. memory is 7.1 GB.
[2020-07-21 16:06:55,880 INFO  L168              Benchmark]: RCFGBuilder took 498.59 ms. Allocated memory was 135.8 MB in the beginning and 201.3 MB in the end (delta: 65.5 MB). Free memory was 89.6 MB in the beginning and 170.2 MB in the end (delta: -80.5 MB). Peak memory consumption was 14.0 MB. Max. memory is 7.1 GB.
[2020-07-21 16:06:55,881 INFO  L168              Benchmark]: TraceAbstraction took 84033.20 ms. Allocated memory was 201.3 MB in the beginning and 313.5 MB in the end (delta: 112.2 MB). Free memory was 169.5 MB in the beginning and 94.8 MB in the end (delta: 74.7 MB). Peak memory consumption was 186.9 MB. Max. memory is 7.1 GB.
[2020-07-21 16:06:55,887 INFO  L336   ainManager$Toolchain]: #######################  End [Toolchain 1] #######################
 --- Results ---
 * Results from de.uni_freiburg.informatik.ultimate.core:
  - StatisticsResult: Toolchain Benchmarks
    Benchmark results are:
 * CDTParser took 0.40 ms. Allocated memory is still 135.8 MB. Free memory was 118.8 MB in the beginning and 118.6 MB in the end (delta: 210.1 kB). Peak memory consumption was 210.1 kB. Max. memory is 7.1 GB.
 * CACSL2BoogieTranslator took 370.79 ms. Allocated memory is still 135.8 MB. Free memory was 100.1 MB in the beginning and 91.0 MB in the end (delta: 9.1 MB). Peak memory consumption was 9.1 MB. Max. memory is 7.1 GB.
 * Boogie Preprocessor took 47.35 ms. Allocated memory is still 135.8 MB. Free memory was 91.0 MB in the beginning and 89.6 MB in the end (delta: 1.4 MB). Peak memory consumption was 1.4 MB. Max. memory is 7.1 GB.
 * RCFGBuilder took 498.59 ms. Allocated memory was 135.8 MB in the beginning and 201.3 MB in the end (delta: 65.5 MB). Free memory was 89.6 MB in the beginning and 170.2 MB in the end (delta: -80.5 MB). Peak memory consumption was 14.0 MB. Max. memory is 7.1 GB.
 * TraceAbstraction took 84033.20 ms. Allocated memory was 201.3 MB in the beginning and 313.5 MB in the end (delta: 112.2 MB). Free memory was 169.5 MB in the beginning and 94.8 MB in the end (delta: 74.7 MB). Peak memory consumption was 186.9 MB. Max. memory is 7.1 GB.
 * Results from de.uni_freiburg.informatik.ultimate.plugins.generator.traceabstraction:
  - CounterExampleResult [Line: 13]: a call of __VERIFIER_error() is reachable
    a call of __VERIFIER_error() is reachable
We found a FailurePath: 
[L10]              unsigned int input = __VERIFIER_nondet_uint();
[L11]  CALL, EXPR  id(input)
       VAL         [\old(x)=20]
[L5]   COND FALSE  !(x==0)
       VAL         [\old(x)=20, x=20]
[L6]   CALL, EXPR  id(x-1)
       VAL         [\old(x)=19]
[L5]   COND FALSE  !(x==0)
       VAL         [\old(x)=19, x=19]
[L6]   CALL, EXPR  id(x-1)
       VAL         [\old(x)=18]
[L5]   COND FALSE  !(x==0)
       VAL         [\old(x)=18, x=18]
[L6]   CALL, EXPR  id(x-1)
       VAL         [\old(x)=17]
[L5]   COND FALSE  !(x==0)
       VAL         [\old(x)=17, x=17]
[L6]   CALL, EXPR  id(x-1)
       VAL         [\old(x)=16]
[L5]   COND FALSE  !(x==0)
       VAL         [\old(x)=16, x=16]
[L6]   CALL, EXPR  id(x-1)
       VAL         [\old(x)=15]
[L5]   COND FALSE  !(x==0)
       VAL         [\old(x)=15, x=15]
[L6]   CALL, EXPR  id(x-1)
       VAL         [\old(x)=14]
[L5]   COND FALSE  !(x==0)
       VAL         [\old(x)=14, x=14]
[L6]   CALL, EXPR  id(x-1)
       VAL         [\old(x)=13]
[L5]   COND FALSE  !(x==0)
       VAL         [\old(x)=13, x=13]
[L6]   CALL, EXPR  id(x-1)
       VAL         [\old(x)=12]
[L5]   COND FALSE  !(x==0)
       VAL         [\old(x)=12, x=12]
[L6]   CALL, EXPR  id(x-1)
       VAL         [\old(x)=11]
[L5]   COND FALSE  !(x==0)
       VAL         [\old(x)=11, x=11]
[L6]   CALL, EXPR  id(x-1)
       VAL         [\old(x)=10]
[L5]   COND FALSE  !(x==0)
       VAL         [\old(x)=10, x=10]
[L6]   CALL, EXPR  id(x-1)
       VAL         [\old(x)=9]
[L5]   COND FALSE  !(x==0)
       VAL         [\old(x)=9, x=9]
[L6]   CALL, EXPR  id(x-1)
       VAL         [\old(x)=8]
[L5]   COND FALSE  !(x==0)
       VAL         [\old(x)=8, x=8]
[L6]   CALL, EXPR  id(x-1)
       VAL         [\old(x)=7]
[L5]   COND FALSE  !(x==0)
       VAL         [\old(x)=7, x=7]
[L6]   CALL, EXPR  id(x-1)
       VAL         [\old(x)=6]
[L5]   COND FALSE  !(x==0)
       VAL         [\old(x)=6, x=6]
[L6]   CALL, EXPR  id(x-1)
       VAL         [\old(x)=5]
[L5]   COND FALSE  !(x==0)
       VAL         [\old(x)=5, x=5]
[L6]   CALL, EXPR  id(x-1)
       VAL         [\old(x)=4]
[L5]   COND FALSE  !(x==0)
       VAL         [\old(x)=4, x=4]
[L6]   CALL, EXPR  id(x-1)
       VAL         [\old(x)=3]
[L5]   COND FALSE  !(x==0)
       VAL         [\old(x)=3, x=3]
[L6]   CALL, EXPR  id(x-1)
       VAL         [\old(x)=2]
[L5]   COND FALSE  !(x==0)
       VAL         [\old(x)=2, x=2]
[L6]   CALL, EXPR  id(x-1)
       VAL         [\old(x)=1]
[L5]   COND FALSE  !(x==0)
       VAL         [\old(x)=1, x=1]
[L6]   CALL, EXPR  id(x-1)
       VAL         [\old(x)=0]
[L5]   COND TRUE   x==0
[L5]               return 0;
       VAL         [\old(x)=0, \result=0, x=0]
[L6]   RET, EXPR   id(x-1)
       VAL         [\old(x)=1, id(x-1)=0, x=1]
[L6]               return id(x-1) + 1;
[L6]   RET, EXPR   id(x-1)
       VAL         [\old(x)=2, id(x-1)=1, x=2]
[L6]               return id(x-1) + 1;
[L6]   RET, EXPR   id(x-1)
       VAL         [\old(x)=3, id(x-1)=2, x=3]
[L6]               return id(x-1) + 1;
[L6]   RET, EXPR   id(x-1)
       VAL         [\old(x)=4, id(x-1)=3, x=4]
[L6]               return id(x-1) + 1;
[L6]   RET, EXPR   id(x-1)
       VAL         [\old(x)=5, id(x-1)=4, x=5]
[L6]               return id(x-1) + 1;
[L6]   RET, EXPR   id(x-1)
       VAL         [\old(x)=6, id(x-1)=5, x=6]
[L6]               return id(x-1) + 1;
[L6]   RET, EXPR   id(x-1)
       VAL         [\old(x)=7, id(x-1)=6, x=7]
[L6]               return id(x-1) + 1;
[L6]   RET, EXPR   id(x-1)
       VAL         [\old(x)=8, id(x-1)=7, x=8]
[L6]               return id(x-1) + 1;
[L6]   RET, EXPR   id(x-1)
       VAL         [\old(x)=9, id(x-1)=8, x=9]
[L6]               return id(x-1) + 1;
[L6]   RET, EXPR   id(x-1)
       VAL         [\old(x)=10, id(x-1)=9, x=10]
[L6]               return id(x-1) + 1;
[L6]   RET, EXPR   id(x-1)
       VAL         [\old(x)=11, id(x-1)=10, x=11]
[L6]               return id(x-1) + 1;
[L6]   RET, EXPR   id(x-1)
       VAL         [\old(x)=12, id(x-1)=11, x=12]
[L6]               return id(x-1) + 1;
[L6]   RET, EXPR   id(x-1)
       VAL         [\old(x)=13, id(x-1)=12, x=13]
[L6]               return id(x-1) + 1;
[L6]   RET, EXPR   id(x-1)
       VAL         [\old(x)=14, id(x-1)=13, x=14]
[L6]               return id(x-1) + 1;
[L6]   RET, EXPR   id(x-1)
       VAL         [\old(x)=15, id(x-1)=14, x=15]
[L6]               return id(x-1) + 1;
[L6]   RET, EXPR   id(x-1)
       VAL         [\old(x)=16, id(x-1)=15, x=16]
[L6]               return id(x-1) + 1;
[L6]   RET, EXPR   id(x-1)
       VAL         [\old(x)=17, id(x-1)=16, x=17]
[L6]               return id(x-1) + 1;
[L6]   RET, EXPR   id(x-1)
       VAL         [\old(x)=18, id(x-1)=17, x=18]
[L6]               return id(x-1) + 1;
[L6]   RET, EXPR   id(x-1)
       VAL         [\old(x)=19, id(x-1)=18, x=19]
[L6]               return id(x-1) + 1;
[L6]   RET, EXPR   id(x-1)
       VAL         [\old(x)=20, id(x-1)=19, x=20]
[L6]               return id(x-1) + 1;
[L11]  RET, EXPR   id(input)
       VAL         [id(input)=20, input=20]
[L11]              unsigned int result = id(input);
[L12]  COND TRUE   result == 20
       VAL         [input=20, result=20]
[L13]              __VERIFIER_error()
       VAL         [input=20, result=20]

  - StatisticsResult: Ultimate Automizer benchmark data
    CFG has 4 procedures, 20 locations, 1 error locations. Started 1 CEGAR loops. VerificationResult: UNSAFE, OverallTime: 83.8s, OverallIterations: 6, TraceHistogramMax: 21, AutomataDifference: 39.8s, DeadEndRemovalTime: 0.0s, HoareAnnotationTime: 0.0s, InitialAbstractionConstructionTime: 0.0s, HoareTripleCheckerStatistics: 131 SDtfs, 2 SDslu, 2197 SDs, 0 SdLazy, 1098 SolverSat, 41 SolverUnsat, 0 SolverUnknown, 0 SolverNotchecked, 1.1s Time, PredicateUnifierStatistics: 0 DeclaredPredicates, 446 GetRequests, 293 SyntacticMatches, 0 SemanticMatches, 153 ConstructedPredicates, 0 IntricatePredicates, 0 DeprecatedPredicates, 719 ImplicationChecksByTransitivity, 74.1s Time, 0.0s BasicInterpolantAutomatonTime, BiggestAbstraction: size=75occurred in iteration=5, traceCheckStatistics: No data available, InterpolantConsolidationStatistics: No data available, PathInvariantsStatistics: No data available, 0/0 InterpolantCoveringCapability, TotalInterpolationStatistics: No data available, 0.0s DumpTime, AutomataMinimizationStatistics: 0.0s AutomataMinimizationTime, 5 MinimizatonAttempts, 0 StatesRemovedByMinimization, 0 NontrivialMinimizations, HoareAnnotationStatistics: No data available, RefinementEngineStatistics: TRACE_CHECK: 0.0s SsaConstructionTime, 1.0s SatisfiabilityAnalysisTime, 41.0s InterpolantComputationTime, 354 NumberOfCodeBlocks, 354 NumberOfCodeBlocksAsserted, 12 NumberOfCheckSat, 420 ConstructedInterpolants, 0 QuantifiedInterpolants, 82734 SizeOfPredicates, 5 NumberOfNonLiveVariables, 462 ConjunctsInSsa, 140 ConjunctsInUnsatCore, 9 InterpolantComputations, 1 PerfectInterpolantSequences, 878/1756 InterpolantCoveringCapability, INVARIANT_SYNTHESIS: No data available, INTERPOLANT_CONSOLIDATION: No data available, ABSTRACT_INTERPRETATION: No data available, PDR: No data available, ACCELERATED_INTERPOLATION: No data available, SIFA: No data available, ReuseStatistics: No data available
RESULT: Ultimate proved your program to be incorrect!
Received shutdown request...