/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_FUNCTIONS --traceabstraction.assert.codeblocks.term.scoring.heuristic.partitioning.strategy FIXED_NUM_PARTITIONS --traceabstraction.assert.codeblocks.term.scoring.heuristic.number.of.partitions 4 -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
[2020-07-20 13:38:27,382 INFO  L177        SettingsManager]: Resetting all preferences to default values...
[2020-07-20 13:38:27,385 INFO  L181        SettingsManager]: Resetting UltimateCore preferences to default values
[2020-07-20 13:38:27,402 INFO  L184        SettingsManager]: Ultimate Commandline Interface provides no preferences, ignoring...
[2020-07-20 13:38:27,402 INFO  L181        SettingsManager]: Resetting Boogie Preprocessor preferences to default values
[2020-07-20 13:38:27,404 INFO  L181        SettingsManager]: Resetting Boogie Procedure Inliner preferences to default values
[2020-07-20 13:38:27,406 INFO  L181        SettingsManager]: Resetting Abstract Interpretation preferences to default values
[2020-07-20 13:38:27,408 INFO  L181        SettingsManager]: Resetting LassoRanker preferences to default values
[2020-07-20 13:38:27,411 INFO  L181        SettingsManager]: Resetting Reaching Definitions preferences to default values
[2020-07-20 13:38:27,412 INFO  L181        SettingsManager]: Resetting SyntaxChecker preferences to default values
[2020-07-20 13:38:27,413 INFO  L181        SettingsManager]: Resetting Sifa preferences to default values
[2020-07-20 13:38:27,415 INFO  L184        SettingsManager]: Büchi Program Product provides no preferences, ignoring...
[2020-07-20 13:38:27,416 INFO  L181        SettingsManager]: Resetting LTL2Aut preferences to default values
[2020-07-20 13:38:27,417 INFO  L181        SettingsManager]: Resetting PEA to Boogie preferences to default values
[2020-07-20 13:38:27,421 INFO  L181        SettingsManager]: Resetting BlockEncodingV2 preferences to default values
[2020-07-20 13:38:27,423 INFO  L181        SettingsManager]: Resetting ChcToBoogie preferences to default values
[2020-07-20 13:38:27,424 INFO  L181        SettingsManager]: Resetting AutomataScriptInterpreter preferences to default values
[2020-07-20 13:38:27,425 INFO  L181        SettingsManager]: Resetting BuchiAutomizer preferences to default values
[2020-07-20 13:38:27,428 INFO  L181        SettingsManager]: Resetting CACSL2BoogieTranslator preferences to default values
[2020-07-20 13:38:27,431 INFO  L181        SettingsManager]: Resetting CodeCheck preferences to default values
[2020-07-20 13:38:27,433 INFO  L181        SettingsManager]: Resetting InvariantSynthesis preferences to default values
[2020-07-20 13:38:27,434 INFO  L181        SettingsManager]: Resetting RCFGBuilder preferences to default values
[2020-07-20 13:38:27,436 INFO  L181        SettingsManager]: Resetting Referee preferences to default values
[2020-07-20 13:38:27,437 INFO  L181        SettingsManager]: Resetting TraceAbstraction preferences to default values
[2020-07-20 13:38:27,440 INFO  L184        SettingsManager]: TraceAbstractionConcurrent provides no preferences, ignoring...
[2020-07-20 13:38:27,441 INFO  L184        SettingsManager]: TraceAbstractionWithAFAs provides no preferences, ignoring...
[2020-07-20 13:38:27,441 INFO  L181        SettingsManager]: Resetting TreeAutomizer preferences to default values
[2020-07-20 13:38:27,443 INFO  L181        SettingsManager]: Resetting IcfgToChc preferences to default values
[2020-07-20 13:38:27,443 INFO  L181        SettingsManager]: Resetting IcfgTransformer preferences to default values
[2020-07-20 13:38:27,445 INFO  L184        SettingsManager]: ReqToTest provides no preferences, ignoring...
[2020-07-20 13:38:27,445 INFO  L181        SettingsManager]: Resetting Boogie Printer preferences to default values
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[2020-07-20 13:38:27,447 INFO  L181        SettingsManager]: Resetting ReqPrinter preferences to default values
[2020-07-20 13:38:27,449 INFO  L181        SettingsManager]: Resetting Witness Printer preferences to default values
[2020-07-20 13:38:27,450 INFO  L184        SettingsManager]: Boogie PL CUP Parser provides no preferences, ignoring...
[2020-07-20 13:38:27,451 INFO  L181        SettingsManager]: Resetting CDTParser preferences to default values
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[2020-07-20 13:38:27,452 INFO  L181        SettingsManager]: Resetting SmtParser preferences to default values
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[2020-07-20 13:38:27,454 INFO  L188        SettingsManager]: Finished resetting all preferences to default values...
[2020-07-20 13:38:27,455 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
[2020-07-20 13:38:27,473 INFO  L113        SettingsManager]: Loading preferences was successful
[2020-07-20 13:38:27,474 INFO  L115        SettingsManager]: Preferences different from defaults after loading the file:
[2020-07-20 13:38:27,476 INFO  L136        SettingsManager]: Preferences of BlockEncodingV2 differ from their defaults:
[2020-07-20 13:38:27,476 INFO  L138        SettingsManager]:  * Create parallel compositions if possible=false
[2020-07-20 13:38:27,476 INFO  L138        SettingsManager]:  * Use SBE=true
[2020-07-20 13:38:27,477 INFO  L136        SettingsManager]: Preferences of CACSL2BoogieTranslator differ from their defaults:
[2020-07-20 13:38:27,477 INFO  L138        SettingsManager]:  * sizeof long=4
[2020-07-20 13:38:27,477 INFO  L138        SettingsManager]:  * Overapproximate operations on floating types=true
[2020-07-20 13:38:27,477 INFO  L138        SettingsManager]:  * sizeof POINTER=4
[2020-07-20 13:38:27,478 INFO  L138        SettingsManager]:  * Check division by zero=IGNORE
[2020-07-20 13:38:27,478 INFO  L138        SettingsManager]:  * Pointer to allocated memory at dereference=IGNORE
[2020-07-20 13:38:27,478 INFO  L138        SettingsManager]:  * If two pointers are subtracted or compared they have the same base address=IGNORE
[2020-07-20 13:38:27,478 INFO  L138        SettingsManager]:  * Check array bounds for arrays that are off heap=IGNORE
[2020-07-20 13:38:27,478 INFO  L138        SettingsManager]:  * sizeof long double=12
[2020-07-20 13:38:27,479 INFO  L138        SettingsManager]:  * Check if freed pointer was valid=false
[2020-07-20 13:38:27,479 INFO  L138        SettingsManager]:  * Use constant arrays=true
[2020-07-20 13:38:27,479 INFO  L138        SettingsManager]:  * Pointer base address is valid at dereference=IGNORE
[2020-07-20 13:38:27,479 INFO  L136        SettingsManager]: Preferences of RCFGBuilder differ from their defaults:
[2020-07-20 13:38:27,479 INFO  L138        SettingsManager]:  * Size of a code block=SequenceOfStatements
[2020-07-20 13:38:27,480 INFO  L138        SettingsManager]:  * To the following directory=./dump/
[2020-07-20 13:38:27,480 INFO  L138        SettingsManager]:  * SMT solver=External_DefaultMode
[2020-07-20 13:38:27,480 INFO  L138        SettingsManager]:  * Command for external solver=z3 SMTLIB2_COMPLIANT=true -memory:2024 -smt2 -in -t:2000
[2020-07-20 13:38:27,480 INFO  L136        SettingsManager]: Preferences of TraceAbstraction differ from their defaults:
[2020-07-20 13:38:27,481 INFO  L138        SettingsManager]:  * Compute Interpolants along a Counterexample=FPandBP
[2020-07-20 13:38:27,481 INFO  L138        SettingsManager]:  * Positions where we compute the Hoare Annotation=LoopsAndPotentialCycles
[2020-07-20 13:38:27,481 INFO  L138        SettingsManager]:  * Trace refinement strategy=CAMEL
[2020-07-20 13:38:27,481 INFO  L138        SettingsManager]:  * Command for external solver=z3 SMTLIB2_COMPLIANT=true -memory:2024 -smt2 -in
[2020-07-20 13:38:27,481 INFO  L138        SettingsManager]:  * Compute Hoare Annotation of negated interpolant automaton, abstraction and CFG=true
[2020-07-20 13:38:27,482 INFO  L138        SettingsManager]:  * Trace refinement exception blacklist=NONE
[2020-07-20 13:38:27,482 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_FUNCTIONS
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 -> 4
[2020-07-20 13:38:27,878 INFO  L81    nceAwareModelManager]: Repository-Root is: /tmp
[2020-07-20 13:38:27,896 INFO  L258   ainManager$Toolchain]: [Toolchain 1]: Applicable parser(s) successfully (re)initialized
[2020-07-20 13:38:27,902 INFO  L214   ainManager$Toolchain]: [Toolchain 1]: Toolchain selected.
[2020-07-20 13:38:27,904 INFO  L271        PluginConnector]: Initializing CDTParser...
[2020-07-20 13:38:27,905 INFO  L275        PluginConnector]: CDTParser initialized
[2020-07-20 13:38:27,906 INFO  L429   ainManager$Toolchain]: [Toolchain 1]: Parsing single file: /storage/repos/ultimate/releaseScripts/default/UAutomizer-linux/../../../trunk/examples/svcomp/recursive-simple/id_o20.c
[2020-07-20 13:38:27,993 INFO  L220              CDTParser]: Created temporary CDT project at /storage/repos/ultimate/releaseScripts/default/UAutomizer-linux/data/1033f33aa/ea78e2ed65aa4cffadcf9b5aae765852/FLAG1e4d54aa5
[2020-07-20 13:38:28,659 INFO  L306              CDTParser]: Found 1 translation units.
[2020-07-20 13:38:28,660 INFO  L160              CDTParser]: Scanning /storage/repos/ultimate/trunk/examples/svcomp/recursive-simple/id_o20.c
[2020-07-20 13:38:28,669 INFO  L349              CDTParser]: About to delete temporary CDT project at /storage/repos/ultimate/releaseScripts/default/UAutomizer-linux/data/1033f33aa/ea78e2ed65aa4cffadcf9b5aae765852/FLAG1e4d54aa5
[2020-07-20 13:38:28,964 INFO  L357              CDTParser]: Successfully deleted /storage/repos/ultimate/releaseScripts/default/UAutomizer-linux/data/1033f33aa/ea78e2ed65aa4cffadcf9b5aae765852
[2020-07-20 13:38:28,978 INFO  L296   ainManager$Toolchain]: ####################### [Toolchain 1] #######################
[2020-07-20 13:38:28,982 INFO  L131        ToolchainWalker]: Walking toolchain with 4 elements.
[2020-07-20 13:38:28,984 INFO  L113        PluginConnector]: ------------------------CACSL2BoogieTranslator----------------------------
[2020-07-20 13:38:28,984 INFO  L271        PluginConnector]: Initializing CACSL2BoogieTranslator...
[2020-07-20 13:38:28,990 INFO  L275        PluginConnector]: CACSL2BoogieTranslator initialized
[2020-07-20 13:38:28,992 INFO  L185        PluginConnector]: Executing the observer ACSLObjectContainerObserver from plugin CACSL2BoogieTranslator for "CDTParser AST 20.07 01:38:28" (1/1) ...
[2020-07-20 13:38:28,997 INFO  L205        PluginConnector]: Invalid model from CACSL2BoogieTranslator for observer de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator.ACSLObjectContainerObserver@ae6d6b0 and model type de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 20.07 01:38:28, skipping insertion in model container
[2020-07-20 13:38:28,997 INFO  L185        PluginConnector]: Executing the observer CACSL2BoogieTranslatorObserver from plugin CACSL2BoogieTranslator for "CDTParser AST 20.07 01:38:28" (1/1) ...
[2020-07-20 13:38:29,008 INFO  L145         MainTranslator]: Starting translation in SV-COMP mode 
[2020-07-20 13:38:29,034 INFO  L178         MainTranslator]: Built tables and reachable declarations
[2020-07-20 13:38:29,292 INFO  L206          PostProcessor]: Analyzing one entry point: main
[2020-07-20 13:38:29,299 INFO  L203         MainTranslator]: Completed pre-run
[2020-07-20 13:38:29,318 INFO  L206          PostProcessor]: Analyzing one entry point: main
[2020-07-20 13:38:29,337 INFO  L208         MainTranslator]: Completed translation
[2020-07-20 13:38:29,338 INFO  L202        PluginConnector]: Adding new model de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 20.07 01:38:29 WrapperNode
[2020-07-20 13:38:29,338 INFO  L132        PluginConnector]: ------------------------ END CACSL2BoogieTranslator----------------------------
[2020-07-20 13:38:29,340 INFO  L113        PluginConnector]: ------------------------Boogie Preprocessor----------------------------
[2020-07-20 13:38:29,340 INFO  L271        PluginConnector]: Initializing Boogie Preprocessor...
[2020-07-20 13:38:29,340 INFO  L275        PluginConnector]: Boogie Preprocessor initialized
[2020-07-20 13:38:29,360 INFO  L185        PluginConnector]: Executing the observer EnsureBoogieModelObserver from plugin Boogie Preprocessor for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 20.07 01:38:29" (1/1) ...
[2020-07-20 13:38:29,361 INFO  L185        PluginConnector]: Executing the observer TypeChecker from plugin Boogie Preprocessor for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 20.07 01:38:29" (1/1) ...
[2020-07-20 13:38:29,369 INFO  L185        PluginConnector]: Executing the observer ConstExpander from plugin Boogie Preprocessor for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 20.07 01:38:29" (1/1) ...
[2020-07-20 13:38:29,370 INFO  L185        PluginConnector]: Executing the observer StructExpander from plugin Boogie Preprocessor for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 20.07 01:38:29" (1/1) ...
[2020-07-20 13:38:29,375 INFO  L185        PluginConnector]: Executing the observer UnstructureCode from plugin Boogie Preprocessor for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 20.07 01:38:29" (1/1) ...
[2020-07-20 13:38:29,378 INFO  L185        PluginConnector]: Executing the observer FunctionInliner from plugin Boogie Preprocessor for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 20.07 01:38:29" (1/1) ...
[2020-07-20 13:38:29,380 INFO  L185        PluginConnector]: Executing the observer BoogieSymbolTableConstructor from plugin Boogie Preprocessor for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 20.07 01:38:29" (1/1) ...
[2020-07-20 13:38:29,382 INFO  L132        PluginConnector]: ------------------------ END Boogie Preprocessor----------------------------
[2020-07-20 13:38:29,383 INFO  L113        PluginConnector]: ------------------------RCFGBuilder----------------------------
[2020-07-20 13:38:29,383 INFO  L271        PluginConnector]: Initializing RCFGBuilder...
[2020-07-20 13:38:29,383 INFO  L275        PluginConnector]: RCFGBuilder initialized
[2020-07-20 13:38:29,385 INFO  L185        PluginConnector]: Executing the observer RCFGBuilderObserver from plugin RCFGBuilder for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 20.07 01:38:29" (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
[2020-07-20 13:38:29,584 INFO  L138     BoogieDeclarations]: Found implementation of procedure ULTIMATE.init
[2020-07-20 13:38:29,584 INFO  L138     BoogieDeclarations]: Found implementation of procedure ULTIMATE.start
[2020-07-20 13:38:29,584 INFO  L138     BoogieDeclarations]: Found implementation of procedure id
[2020-07-20 13:38:29,584 INFO  L138     BoogieDeclarations]: Found implementation of procedure main
[2020-07-20 13:38:29,585 INFO  L130     BoogieDeclarations]: Found specification of procedure __VERIFIER_nondet_uint
[2020-07-20 13:38:29,585 INFO  L130     BoogieDeclarations]: Found specification of procedure __VERIFIER_error
[2020-07-20 13:38:29,585 INFO  L130     BoogieDeclarations]: Found specification of procedure id
[2020-07-20 13:38:29,585 INFO  L130     BoogieDeclarations]: Found specification of procedure main
[2020-07-20 13:38:29,586 INFO  L130     BoogieDeclarations]: Found specification of procedure ULTIMATE.init
[2020-07-20 13:38:29,586 INFO  L130     BoogieDeclarations]: Found specification of procedure ULTIMATE.start
[2020-07-20 13:38:29,787 INFO  L290             CfgBuilder]: Using the 1 location(s) as analysis (start of procedure ULTIMATE.start)
[2020-07-20 13:38:29,788 INFO  L295             CfgBuilder]: Removed 0 assume(true) statements.
[2020-07-20 13:38:29,793 INFO  L202        PluginConnector]: Adding new model de.uni_freiburg.informatik.ultimate.plugins.generator.rcfgbuilder CFG 20.07 01:38:29 BoogieIcfgContainer
[2020-07-20 13:38:29,793 INFO  L132        PluginConnector]: ------------------------ END RCFGBuilder----------------------------
[2020-07-20 13:38:29,795 INFO  L113        PluginConnector]: ------------------------TraceAbstraction----------------------------
[2020-07-20 13:38:29,795 INFO  L271        PluginConnector]: Initializing TraceAbstraction...
[2020-07-20 13:38:29,800 INFO  L275        PluginConnector]: TraceAbstraction initialized
[2020-07-20 13:38:29,801 INFO  L185        PluginConnector]: Executing the observer TraceAbstractionObserver from plugin TraceAbstraction for "CDTParser AST 20.07 01:38:28" (1/3) ...
[2020-07-20 13:38:29,805 INFO  L205        PluginConnector]: Invalid model from TraceAbstraction for observer de.uni_freiburg.informatik.ultimate.plugins.generator.traceabstraction.TraceAbstractionObserver@147791d5 and model type de.uni_freiburg.informatik.ultimate.plugins.generator.traceabstraction AST 20.07 01:38:29, skipping insertion in model container
[2020-07-20 13:38:29,805 INFO  L185        PluginConnector]: Executing the observer TraceAbstractionObserver from plugin TraceAbstraction for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 20.07 01:38:29" (2/3) ...
[2020-07-20 13:38:29,806 INFO  L205        PluginConnector]: Invalid model from TraceAbstraction for observer de.uni_freiburg.informatik.ultimate.plugins.generator.traceabstraction.TraceAbstractionObserver@147791d5 and model type de.uni_freiburg.informatik.ultimate.plugins.generator.traceabstraction AST 20.07 01:38:29, skipping insertion in model container
[2020-07-20 13:38:29,807 INFO  L185        PluginConnector]: Executing the observer TraceAbstractionObserver from plugin TraceAbstraction for "de.uni_freiburg.informatik.ultimate.plugins.generator.rcfgbuilder CFG 20.07 01:38:29" (3/3) ...
[2020-07-20 13:38:29,809 INFO  L109   eAbstractionObserver]: Analyzing ICFG id_o20.c
[2020-07-20 13:38:29,825 INFO  L157   ceAbstractionStarter]: Automizer settings: Hoare:true NWA Interpolation:FPandBPonlyIfFpWasNotPerfect Determinization: PREDICATE_ABSTRACTION
[2020-07-20 13:38:29,839 INFO  L169   ceAbstractionStarter]: Appying trace abstraction to program that has 1 error locations.
[2020-07-20 13:38:29,856 INFO  L251      AbstractCegarLoop]: Starting to check reachability of 1 error locations.
[2020-07-20 13:38:29,887 INFO  L375      AbstractCegarLoop]: Interprodecural is true
[2020-07-20 13:38:29,888 INFO  L376      AbstractCegarLoop]: Hoare is true
[2020-07-20 13:38:29,888 INFO  L377      AbstractCegarLoop]: Compute interpolants for FPandBPonlyIfFpWasNotPerfect
[2020-07-20 13:38:29,888 INFO  L378      AbstractCegarLoop]: Backedges is STRAIGHT_LINE
[2020-07-20 13:38:29,888 INFO  L379      AbstractCegarLoop]: Determinization is PREDICATE_ABSTRACTION
[2020-07-20 13:38:29,889 INFO  L380      AbstractCegarLoop]: Difference is false
[2020-07-20 13:38:29,889 INFO  L381      AbstractCegarLoop]: Minimize is MINIMIZE_SEVPA
[2020-07-20 13:38:29,889 INFO  L385      AbstractCegarLoop]: ======== Iteration 0==of CEGAR loop == AllErrorsAtOnce========
[2020-07-20 13:38:29,911 INFO  L276                IsEmpty]: Start isEmpty. Operand 20 states.
[2020-07-20 13:38:29,921 INFO  L282                IsEmpty]: Finished isEmpty. Found accepting run of length 14
[2020-07-20 13:38:29,921 INFO  L414         BasicCegarLoop]: Found error trace
[2020-07-20 13:38:29,923 INFO  L422         BasicCegarLoop]: trace histogram [1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1]
[2020-07-20 13:38:29,924 INFO  L427      AbstractCegarLoop]: === Iteration 1 === [mainErr0ASSERT_VIOLATIONERROR_FUNCTION]===
[2020-07-20 13:38:29,933 INFO  L144       PredicateUnifier]: Initialized classic predicate unifier
[2020-07-20 13:38:29,935 INFO  L82        PathProgramCache]: Analyzing trace with hash -872342019, now seen corresponding path program 1 times
[2020-07-20 13:38:29,947 INFO  L163   FreeRefinementEngine]: Executing refinement strategy FIXED_PREFERENCES
[2020-07-20 13:38:29,948 INFO  L354   FreeRefinementEngine]: Using trace check IpTcStrategyModulePreferences [330976825]
[2020-07-20 13:38:29,948 INFO  L95    rtionOrderModulation]: Keeping assertion order SMT_FEATURE_HEURISTIC (partitioning type FIXED_NUM_PARTITIONS, 4 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
[2020-07-20 13:38:30,047 INFO  L228   tOrderPrioritization]: Assert order SMT_FEATURE_HEURISTIC (partitioning type FIXED_NUM_PARTITIONS, 4 partitions) issued 3 check-sat command(s)
[2020-07-20 13:38:30,047 INFO  L229   tOrderPrioritization]: Conjunction of SSA is unsat
[2020-07-20 13:38:30,051 INFO  L263         TraceCheckSpWp]: Trace formula consists of 29 conjuncts, 7 conjunts are in the unsatisfiable core
[2020-07-20 13:38:30,060 INFO  L286         TraceCheckSpWp]: Computing forward predicates...
[2020-07-20 13:38:30,190 INFO  L134       CoverageAnalysis]: Checked inductivity of 0 backedges. 0 proven. 0 refuted. 0 times theorem prover too weak. 0 trivial. 0 not checked.
[2020-07-20 13:38:30,191 INFO  L324         TraceCheckSpWp]: Omiting computation of backward sequence because forward sequence was already perfect
[2020-07-20 13:38:30,193 INFO  L354   FreeRefinementEngine]: Using interpolant generator IpTcStrategyModulePreferences [330976825]
[2020-07-20 13:38:30,194 INFO  L220   FreeRefinementEngine]: Constructing automaton from 1 perfect and 0 imperfect interpolant sequences.
[2020-07-20 13:38:30,195 INFO  L233   FreeRefinementEngine]: Number of different interpolants: perfect sequences [5] imperfect sequences [] total 5
[2020-07-20 13:38:30,197 INFO  L156   tionRefinementEngine]: Using interpolant automaton builder IpAbStrategyModuleStraightlineAll [1378817948]
[2020-07-20 13:38:30,205 INFO  L459      AbstractCegarLoop]: Interpolant automaton has 5 states
[2020-07-20 13:38:30,206 INFO  L143   FreeRefinementEngine]: Using predicate unifier PredicateUnifier provided by strategy FIXED_PREFERENCES
[2020-07-20 13:38:30,226 INFO  L142   InterpolantAutomaton]: Constructing interpolant automaton starting with 5 interpolants.
[2020-07-20 13:38:30,227 INFO  L144   InterpolantAutomaton]: CoverageRelationStatistics Valid=7, Invalid=13, Unknown=0, NotChecked=0, Total=20
[2020-07-20 13:38:30,230 INFO  L87              Difference]: Start difference. First operand 20 states. Second operand 5 states.
[2020-07-20 13:38:30,315 INFO  L144             Difference]: Subtrahend was deterministic. Have not used determinization.
[2020-07-20 13:38:30,316 INFO  L93              Difference]: Finished difference Result 32 states and 35 transitions.
[2020-07-20 13:38:30,317 INFO  L141   InterpolantAutomaton]: Switched to read-only mode: deterministic interpolant automaton has 5 states. 
[2020-07-20 13:38:30,319 INFO  L78                 Accepts]: Start accepts. Automaton has 5 states. Word has length 13
[2020-07-20 13:38:30,320 INFO  L84                 Accepts]: Finished accepts. some prefix is accepted.
[2020-07-20 13:38:30,332 INFO  L225             Difference]: With dead ends: 32
[2020-07-20 13:38:30,332 INFO  L226             Difference]: Without dead ends: 18
[2020-07-20 13:38:30,336 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
[2020-07-20 13:38:30,355 INFO  L82        GeneralOperation]: Start minimizeSevpa. Operand 18 states.
[2020-07-20 13:38:30,379 INFO  L88        GeneralOperation]: Finished minimizeSevpa. Reduced states from 18 to 18.
[2020-07-20 13:38:30,381 INFO  L82        GeneralOperation]: Start removeUnreachable. Operand 18 states.
[2020-07-20 13:38:30,382 INFO  L88        GeneralOperation]: Finished removeUnreachable. Reduced from 18 states to 18 states and 19 transitions.
[2020-07-20 13:38:30,385 INFO  L78                 Accepts]: Start accepts. Automaton has 18 states and 19 transitions. Word has length 13
[2020-07-20 13:38:30,385 INFO  L84                 Accepts]: Finished accepts. word is rejected.
[2020-07-20 13:38:30,386 INFO  L479      AbstractCegarLoop]: Abstraction has 18 states and 19 transitions.
[2020-07-20 13:38:30,386 INFO  L480      AbstractCegarLoop]: Interpolant automaton has 5 states.
[2020-07-20 13:38:30,386 INFO  L276                IsEmpty]: Start isEmpty. Operand 18 states and 19 transitions.
[2020-07-20 13:38:30,388 INFO  L282                IsEmpty]: Finished isEmpty. Found accepting run of length 20
[2020-07-20 13:38:30,389 INFO  L414         BasicCegarLoop]: Found error trace
[2020-07-20 13:38:30,389 INFO  L422         BasicCegarLoop]: trace histogram [2, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1]
[2020-07-20 13:38:30,604 WARN  L516      AbstractCegarLoop]: Destroyed unattended storables created during the last iteration: 2 z3 SMTLIB2_COMPLIANT=true -memory:2024 -smt2 -in
[2020-07-20 13:38:30,609 INFO  L427      AbstractCegarLoop]: === Iteration 2 === [mainErr0ASSERT_VIOLATIONERROR_FUNCTION]===
[2020-07-20 13:38:30,610 INFO  L144       PredicateUnifier]: Initialized classic predicate unifier
[2020-07-20 13:38:30,610 INFO  L82        PathProgramCache]: Analyzing trace with hash -953570577, now seen corresponding path program 1 times
[2020-07-20 13:38:30,611 INFO  L163   FreeRefinementEngine]: Executing refinement strategy FIXED_PREFERENCES
[2020-07-20 13:38:30,611 INFO  L354   FreeRefinementEngine]: Using trace check IpTcStrategyModulePreferences [2011649663]
[2020-07-20 13:38:30,612 INFO  L95    rtionOrderModulation]: Keeping assertion order SMT_FEATURE_HEURISTIC (partitioning type FIXED_NUM_PARTITIONS, 4 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
[2020-07-20 13:38:30,655 INFO  L228   tOrderPrioritization]: Assert order SMT_FEATURE_HEURISTIC (partitioning type FIXED_NUM_PARTITIONS, 4 partitions) issued 4 check-sat command(s)
[2020-07-20 13:38:30,656 INFO  L229   tOrderPrioritization]: Conjunction of SSA is unsat
[2020-07-20 13:38:30,658 INFO  L263         TraceCheckSpWp]: Trace formula consists of 42 conjuncts, 11 conjunts are in the unsatisfiable core
[2020-07-20 13:38:30,661 INFO  L286         TraceCheckSpWp]: Computing forward predicates...
[2020-07-20 13:38:30,740 INFO  L134       CoverageAnalysis]: Checked inductivity of 4 backedges. 0 proven. 2 refuted. 0 times theorem prover too weak. 2 trivial. 0 not checked.
[2020-07-20 13:38:30,740 INFO  L328         TraceCheckSpWp]: Computing backward predicates...
[2020-07-20 13:38:30,988 INFO  L134       CoverageAnalysis]: Checked inductivity of 4 backedges. 0 proven. 2 refuted. 0 times theorem prover too weak. 2 trivial. 0 not checked.
[2020-07-20 13:38:30,989 INFO  L354   FreeRefinementEngine]: Using interpolant generator IpTcStrategyModulePreferences [2011649663]
[2020-07-20 13:38:30,990 INFO  L220   FreeRefinementEngine]: Constructing automaton from 0 perfect and 2 imperfect interpolant sequences.
[2020-07-20 13:38:30,990 INFO  L233   FreeRefinementEngine]: Number of different interpolants: perfect sequences [] imperfect sequences [7, 7] total 12
[2020-07-20 13:38:30,991 INFO  L156   tionRefinementEngine]: Using interpolant automaton builder IpAbStrategyModuleStraightlineAll [65446081]
[2020-07-20 13:38:30,993 INFO  L459      AbstractCegarLoop]: Interpolant automaton has 12 states
[2020-07-20 13:38:30,994 INFO  L143   FreeRefinementEngine]: Using predicate unifier PredicateUnifier provided by strategy FIXED_PREFERENCES
[2020-07-20 13:38:30,994 INFO  L142   InterpolantAutomaton]: Constructing interpolant automaton starting with 12 interpolants.
[2020-07-20 13:38:30,995 INFO  L144   InterpolantAutomaton]: CoverageRelationStatistics Valid=28, Invalid=104, Unknown=0, NotChecked=0, Total=132
[2020-07-20 13:38:30,996 INFO  L87              Difference]: Start difference. First operand 18 states and 19 transitions. Second operand 12 states.
[2020-07-20 13:38:31,070 INFO  L144             Difference]: Subtrahend was deterministic. Have not used determinization.
[2020-07-20 13:38:31,070 INFO  L93              Difference]: Finished difference Result 30 states and 32 transitions.
[2020-07-20 13:38:31,071 INFO  L141   InterpolantAutomaton]: Switched to read-only mode: deterministic interpolant automaton has 11 states. 
[2020-07-20 13:38:31,072 INFO  L78                 Accepts]: Start accepts. Automaton has 12 states. Word has length 19
[2020-07-20 13:38:31,072 INFO  L84                 Accepts]: Finished accepts. some prefix is accepted.
[2020-07-20 13:38:31,073 INFO  L225             Difference]: With dead ends: 30
[2020-07-20 13:38:31,074 INFO  L226             Difference]: Without dead ends: 24
[2020-07-20 13:38:31,076 INFO  L675         BasicCegarLoop]: 0 DeclaredPredicates, 37 GetRequests, 27 SyntacticMatches, 0 SemanticMatches, 10 ConstructedPredicates, 0 IntricatePredicates, 0 DeprecatedPredicates, 9 ImplicationChecksByTransitivity, 0.1s TimeCoverageRelationStatistics Valid=28, Invalid=104, Unknown=0, NotChecked=0, Total=132
[2020-07-20 13:38:31,076 INFO  L82        GeneralOperation]: Start minimizeSevpa. Operand 24 states.
[2020-07-20 13:38:31,083 INFO  L88        GeneralOperation]: Finished minimizeSevpa. Reduced states from 24 to 24.
[2020-07-20 13:38:31,083 INFO  L82        GeneralOperation]: Start removeUnreachable. Operand 24 states.
[2020-07-20 13:38:31,084 INFO  L88        GeneralOperation]: Finished removeUnreachable. Reduced from 24 states to 24 states and 25 transitions.
[2020-07-20 13:38:31,085 INFO  L78                 Accepts]: Start accepts. Automaton has 24 states and 25 transitions. Word has length 19
[2020-07-20 13:38:31,085 INFO  L84                 Accepts]: Finished accepts. word is rejected.
[2020-07-20 13:38:31,086 INFO  L479      AbstractCegarLoop]: Abstraction has 24 states and 25 transitions.
[2020-07-20 13:38:31,086 INFO  L480      AbstractCegarLoop]: Interpolant automaton has 12 states.
[2020-07-20 13:38:31,086 INFO  L276                IsEmpty]: Start isEmpty. Operand 24 states and 25 transitions.
[2020-07-20 13:38:31,087 INFO  L282                IsEmpty]: Finished isEmpty. Found accepting run of length 32
[2020-07-20 13:38:31,087 INFO  L414         BasicCegarLoop]: Found error trace
[2020-07-20 13:38:31,088 INFO  L422         BasicCegarLoop]: trace histogram [4, 4, 3, 3, 3, 3, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1]
[2020-07-20 13:38:31,300 WARN  L516      AbstractCegarLoop]: Destroyed unattended storables created during the last iteration: 3 z3 SMTLIB2_COMPLIANT=true -memory:2024 -smt2 -in
[2020-07-20 13:38:31,301 INFO  L427      AbstractCegarLoop]: === Iteration 3 === [mainErr0ASSERT_VIOLATIONERROR_FUNCTION]===
[2020-07-20 13:38:31,302 INFO  L144       PredicateUnifier]: Initialized classic predicate unifier
[2020-07-20 13:38:31,302 INFO  L82        PathProgramCache]: Analyzing trace with hash 1198310127, now seen corresponding path program 2 times
[2020-07-20 13:38:31,303 INFO  L163   FreeRefinementEngine]: Executing refinement strategy FIXED_PREFERENCES
[2020-07-20 13:38:31,303 INFO  L354   FreeRefinementEngine]: Using trace check IpTcStrategyModulePreferences [1251413101]
[2020-07-20 13:38:31,303 INFO  L95    rtionOrderModulation]: Keeping assertion order SMT_FEATURE_HEURISTIC (partitioning type FIXED_NUM_PARTITIONS, 4 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
[2020-07-20 13:38:31,352 INFO  L228   tOrderPrioritization]: Assert order SMT_FEATURE_HEURISTIC (partitioning type FIXED_NUM_PARTITIONS, 4 partitions) issued 4 check-sat command(s)
[2020-07-20 13:38:31,353 INFO  L229   tOrderPrioritization]: Conjunction of SSA is unsat
[2020-07-20 13:38:31,355 INFO  L263         TraceCheckSpWp]: Trace formula consists of 66 conjuncts, 19 conjunts are in the unsatisfiable core
[2020-07-20 13:38:31,359 INFO  L286         TraceCheckSpWp]: Computing forward predicates...
[2020-07-20 13:38:31,489 INFO  L134       CoverageAnalysis]: Checked inductivity of 30 backedges. 0 proven. 15 refuted. 0 times theorem prover too weak. 15 trivial. 0 not checked.
[2020-07-20 13:38:31,490 INFO  L328         TraceCheckSpWp]: Computing backward predicates...
[2020-07-20 13:38:32,016 INFO  L134       CoverageAnalysis]: Checked inductivity of 30 backedges. 0 proven. 15 refuted. 0 times theorem prover too weak. 15 trivial. 0 not checked.
[2020-07-20 13:38:32,017 INFO  L354   FreeRefinementEngine]: Using interpolant generator IpTcStrategyModulePreferences [1251413101]
[2020-07-20 13:38:32,017 INFO  L220   FreeRefinementEngine]: Constructing automaton from 0 perfect and 2 imperfect interpolant sequences.
[2020-07-20 13:38:32,017 INFO  L233   FreeRefinementEngine]: Number of different interpolants: perfect sequences [] imperfect sequences [11, 11] total 20
[2020-07-20 13:38:32,018 INFO  L156   tionRefinementEngine]: Using interpolant automaton builder IpAbStrategyModuleStraightlineAll [1949558980]
[2020-07-20 13:38:32,018 INFO  L459      AbstractCegarLoop]: Interpolant automaton has 20 states
[2020-07-20 13:38:32,019 INFO  L143   FreeRefinementEngine]: Using predicate unifier PredicateUnifier provided by strategy FIXED_PREFERENCES
[2020-07-20 13:38:32,019 INFO  L142   InterpolantAutomaton]: Constructing interpolant automaton starting with 20 interpolants.
[2020-07-20 13:38:32,020 INFO  L144   InterpolantAutomaton]: CoverageRelationStatistics Valid=64, Invalid=316, Unknown=0, NotChecked=0, Total=380
[2020-07-20 13:38:32,020 INFO  L87              Difference]: Start difference. First operand 24 states and 25 transitions. Second operand 20 states.
[2020-07-20 13:38:34,491 WARN  L193               SmtUtils]: Spent 2.21 s on a formula simplification. DAG size of input: 16 DAG size of output: 11
[2020-07-20 13:38:36,809 INFO  L144             Difference]: Subtrahend was deterministic. Have not used determinization.
[2020-07-20 13:38:36,810 INFO  L93              Difference]: Finished difference Result 42 states and 46 transitions.
[2020-07-20 13:38:36,810 INFO  L141   InterpolantAutomaton]: Switched to read-only mode: deterministic interpolant automaton has 19 states. 
[2020-07-20 13:38:36,811 INFO  L78                 Accepts]: Start accepts. Automaton has 20 states. Word has length 31
[2020-07-20 13:38:36,811 INFO  L84                 Accepts]: Finished accepts. some prefix is accepted.
[2020-07-20 13:38:36,813 INFO  L225             Difference]: With dead ends: 42
[2020-07-20 13:38:36,813 INFO  L226             Difference]: Without dead ends: 36
[2020-07-20 13:38:36,817 INFO  L675         BasicCegarLoop]: 0 DeclaredPredicates, 65 GetRequests, 43 SyntacticMatches, 0 SemanticMatches, 22 ConstructedPredicates, 0 IntricatePredicates, 0 DeprecatedPredicates, 32 ImplicationChecksByTransitivity, 4.9s TimeCoverageRelationStatistics Valid=98, Invalid=453, Unknown=1, NotChecked=0, Total=552
[2020-07-20 13:38:36,818 INFO  L82        GeneralOperation]: Start minimizeSevpa. Operand 36 states.
[2020-07-20 13:38:36,825 INFO  L88        GeneralOperation]: Finished minimizeSevpa. Reduced states from 36 to 36.
[2020-07-20 13:38:36,826 INFO  L82        GeneralOperation]: Start removeUnreachable. Operand 36 states.
[2020-07-20 13:38:36,827 INFO  L88        GeneralOperation]: Finished removeUnreachable. Reduced from 36 states to 36 states and 37 transitions.
[2020-07-20 13:38:36,828 INFO  L78                 Accepts]: Start accepts. Automaton has 36 states and 37 transitions. Word has length 31
[2020-07-20 13:38:36,828 INFO  L84                 Accepts]: Finished accepts. word is rejected.
[2020-07-20 13:38:36,828 INFO  L479      AbstractCegarLoop]: Abstraction has 36 states and 37 transitions.
[2020-07-20 13:38:36,828 INFO  L480      AbstractCegarLoop]: Interpolant automaton has 20 states.
[2020-07-20 13:38:36,829 INFO  L276                IsEmpty]: Start isEmpty. Operand 36 states and 37 transitions.
[2020-07-20 13:38:36,831 INFO  L282                IsEmpty]: Finished isEmpty. Found accepting run of length 56
[2020-07-20 13:38:36,831 INFO  L414         BasicCegarLoop]: Found error trace
[2020-07-20 13:38:36,831 INFO  L422         BasicCegarLoop]: trace histogram [8, 8, 7, 7, 7, 7, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1]
[2020-07-20 13:38:37,045 WARN  L516      AbstractCegarLoop]: Destroyed unattended storables created during the last iteration: 4 z3 SMTLIB2_COMPLIANT=true -memory:2024 -smt2 -in
[2020-07-20 13:38:37,047 INFO  L427      AbstractCegarLoop]: === Iteration 4 === [mainErr0ASSERT_VIOLATIONERROR_FUNCTION]===
[2020-07-20 13:38:37,047 INFO  L144       PredicateUnifier]: Initialized classic predicate unifier
[2020-07-20 13:38:37,048 INFO  L82        PathProgramCache]: Analyzing trace with hash 1532150511, now seen corresponding path program 3 times
[2020-07-20 13:38:37,049 INFO  L163   FreeRefinementEngine]: Executing refinement strategy FIXED_PREFERENCES
[2020-07-20 13:38:37,049 INFO  L354   FreeRefinementEngine]: Using trace check IpTcStrategyModulePreferences [740507373]
[2020-07-20 13:38:37,050 INFO  L95    rtionOrderModulation]: Keeping assertion order SMT_FEATURE_HEURISTIC (partitioning type FIXED_NUM_PARTITIONS, 4 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
[2020-07-20 13:38:37,144 INFO  L228   tOrderPrioritization]: Assert order SMT_FEATURE_HEURISTIC (partitioning type FIXED_NUM_PARTITIONS, 4 partitions) issued 4 check-sat command(s)
[2020-07-20 13:38:37,145 INFO  L229   tOrderPrioritization]: Conjunction of SSA is unsat
[2020-07-20 13:38:37,147 INFO  L263         TraceCheckSpWp]: Trace formula consists of 114 conjuncts, 35 conjunts are in the unsatisfiable core
[2020-07-20 13:38:37,152 INFO  L286         TraceCheckSpWp]: Computing forward predicates...
[2020-07-20 13:38:37,431 INFO  L134       CoverageAnalysis]: Checked inductivity of 154 backedges. 0 proven. 77 refuted. 0 times theorem prover too weak. 77 trivial. 0 not checked.
[2020-07-20 13:38:37,432 INFO  L328         TraceCheckSpWp]: Computing backward predicates...
[2020-07-20 13:38:47,713 INFO  L134       CoverageAnalysis]: Checked inductivity of 154 backedges. 0 proven. 74 refuted. 3 times theorem prover too weak. 77 trivial. 0 not checked.
[2020-07-20 13:38:47,714 INFO  L354   FreeRefinementEngine]: Using interpolant generator IpTcStrategyModulePreferences [740507373]
[2020-07-20 13:38:47,714 INFO  L220   FreeRefinementEngine]: Constructing automaton from 0 perfect and 2 imperfect interpolant sequences.
[2020-07-20 13:38:47,715 INFO  L233   FreeRefinementEngine]: Number of different interpolants: perfect sequences [] imperfect sequences [19, 19] total 36
[2020-07-20 13:38:47,715 INFO  L156   tionRefinementEngine]: Using interpolant automaton builder IpAbStrategyModuleStraightlineAll [2114529059]
[2020-07-20 13:38:47,716 INFO  L459      AbstractCegarLoop]: Interpolant automaton has 36 states
[2020-07-20 13:38:47,717 INFO  L143   FreeRefinementEngine]: Using predicate unifier PredicateUnifier provided by strategy FIXED_PREFERENCES
[2020-07-20 13:38:47,717 INFO  L142   InterpolantAutomaton]: Constructing interpolant automaton starting with 36 interpolants.
[2020-07-20 13:38:47,718 INFO  L144   InterpolantAutomaton]: CoverageRelationStatistics Valid=184, Invalid=1072, Unknown=4, NotChecked=0, Total=1260
[2020-07-20 13:38:47,719 INFO  L87              Difference]: Start difference. First operand 36 states and 37 transitions. Second operand 36 states.
[2020-07-20 13:38:48,525 WARN  L193               SmtUtils]: Spent 111.00 ms on a formula simplification. DAG size of input: 38 DAG size of output: 13
[2020-07-20 13:38:51,091 WARN  L193               SmtUtils]: Spent 2.13 s on a formula simplification. DAG size of input: 36 DAG size of output: 11
[2020-07-20 13:38:52,144 WARN  L193               SmtUtils]: Spent 130.00 ms on a formula simplification. DAG size of input: 31 DAG size of output: 11
[2020-07-20 13:38:56,608 WARN  L193               SmtUtils]: Spent 4.21 s on a formula simplification. DAG size of input: 28 DAG size of output: 13
[2020-07-20 13:38:59,007 WARN  L193               SmtUtils]: Spent 2.13 s on a formula simplification. DAG size of input: 26 DAG size of output: 11
[2020-07-20 13:39:18,756 INFO  L144             Difference]: Subtrahend was deterministic. Have not used determinization.
[2020-07-20 13:39:18,757 INFO  L93              Difference]: Finished difference Result 66 states and 74 transitions.
[2020-07-20 13:39:18,760 INFO  L141   InterpolantAutomaton]: Switched to read-only mode: deterministic interpolant automaton has 35 states. 
[2020-07-20 13:39:18,761 INFO  L78                 Accepts]: Start accepts. Automaton has 36 states. Word has length 55
[2020-07-20 13:39:18,761 INFO  L84                 Accepts]: Finished accepts. some prefix is accepted.
[2020-07-20 13:39:18,763 INFO  L225             Difference]: With dead ends: 66
[2020-07-20 13:39:18,763 INFO  L226             Difference]: Without dead ends: 60
[2020-07-20 13:39:18,766 INFO  L675         BasicCegarLoop]: 0 DeclaredPredicates, 121 GetRequests, 75 SyntacticMatches, 0 SemanticMatches, 46 ConstructedPredicates, 0 IntricatePredicates, 0 DeprecatedPredicates, 156 ImplicationChecksByTransitivity, 36.1s TimeCoverageRelationStatistics Valid=380, Invalid=1869, Unknown=7, NotChecked=0, Total=2256
[2020-07-20 13:39:18,766 INFO  L82        GeneralOperation]: Start minimizeSevpa. Operand 60 states.
[2020-07-20 13:39:18,776 INFO  L88        GeneralOperation]: Finished minimizeSevpa. Reduced states from 60 to 60.
[2020-07-20 13:39:18,776 INFO  L82        GeneralOperation]: Start removeUnreachable. Operand 60 states.
[2020-07-20 13:39:18,778 INFO  L88        GeneralOperation]: Finished removeUnreachable. Reduced from 60 states to 60 states and 61 transitions.
[2020-07-20 13:39:18,779 INFO  L78                 Accepts]: Start accepts. Automaton has 60 states and 61 transitions. Word has length 55
[2020-07-20 13:39:18,779 INFO  L84                 Accepts]: Finished accepts. word is rejected.
[2020-07-20 13:39:18,780 INFO  L479      AbstractCegarLoop]: Abstraction has 60 states and 61 transitions.
[2020-07-20 13:39:18,780 INFO  L480      AbstractCegarLoop]: Interpolant automaton has 36 states.
[2020-07-20 13:39:18,780 INFO  L276                IsEmpty]: Start isEmpty. Operand 60 states and 61 transitions.
[2020-07-20 13:39:18,784 INFO  L282                IsEmpty]: Finished isEmpty. Found accepting run of length 104
[2020-07-20 13:39:18,785 INFO  L414         BasicCegarLoop]: Found error trace
[2020-07-20 13:39:18,785 INFO  L422         BasicCegarLoop]: trace histogram [16, 16, 15, 15, 15, 15, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1]
[2020-07-20 13:39:18,990 WARN  L516      AbstractCegarLoop]: Destroyed unattended storables created during the last iteration: 5 z3 SMTLIB2_COMPLIANT=true -memory:2024 -smt2 -in
[2020-07-20 13:39:18,991 INFO  L427      AbstractCegarLoop]: === Iteration 5 === [mainErr0ASSERT_VIOLATIONERROR_FUNCTION]===
[2020-07-20 13:39:18,991 INFO  L144       PredicateUnifier]: Initialized classic predicate unifier
[2020-07-20 13:39:18,992 INFO  L82        PathProgramCache]: Analyzing trace with hash 1083048687, now seen corresponding path program 4 times
[2020-07-20 13:39:18,993 INFO  L163   FreeRefinementEngine]: Executing refinement strategy FIXED_PREFERENCES
[2020-07-20 13:39:18,993 INFO  L354   FreeRefinementEngine]: Using trace check IpTcStrategyModulePreferences [1295308868]
[2020-07-20 13:39:18,994 INFO  L95    rtionOrderModulation]: Keeping assertion order SMT_FEATURE_HEURISTIC (partitioning type FIXED_NUM_PARTITIONS, 4 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
[2020-07-20 13:39:20,429 INFO  L228   tOrderPrioritization]: Assert order SMT_FEATURE_HEURISTIC (partitioning type FIXED_NUM_PARTITIONS, 4 partitions) issued 4 check-sat command(s)
[2020-07-20 13:39:20,430 INFO  L229   tOrderPrioritization]: Conjunction of SSA is unsat
[2020-07-20 13:39:20,434 INFO  L263         TraceCheckSpWp]: Trace formula consists of 210 conjuncts, 67 conjunts are in the unsatisfiable core
[2020-07-20 13:39:20,441 INFO  L286         TraceCheckSpWp]: Computing forward predicates...
[2020-07-20 13:39:21,228 INFO  L134       CoverageAnalysis]: Checked inductivity of 690 backedges. 0 proven. 345 refuted. 0 times theorem prover too weak. 345 trivial. 0 not checked.
[2020-07-20 13:39:21,228 INFO  L328         TraceCheckSpWp]: Computing backward predicates...
[2020-07-20 13:39:41,654 INFO  L134       CoverageAnalysis]: Checked inductivity of 690 backedges. 0 proven. 345 refuted. 0 times theorem prover too weak. 345 trivial. 0 not checked.
[2020-07-20 13:39:41,654 INFO  L354   FreeRefinementEngine]: Using interpolant generator IpTcStrategyModulePreferences [1295308868]
[2020-07-20 13:39:41,655 INFO  L220   FreeRefinementEngine]: Constructing automaton from 0 perfect and 2 imperfect interpolant sequences.
[2020-07-20 13:39:41,655 INFO  L233   FreeRefinementEngine]: Number of different interpolants: perfect sequences [] imperfect sequences [35, 35] total 68
[2020-07-20 13:39:41,655 INFO  L156   tionRefinementEngine]: Using interpolant automaton builder IpAbStrategyModuleStraightlineAll [426966786]
[2020-07-20 13:39:41,659 INFO  L459      AbstractCegarLoop]: Interpolant automaton has 68 states
[2020-07-20 13:39:41,660 INFO  L143   FreeRefinementEngine]: Using predicate unifier PredicateUnifier provided by strategy FIXED_PREFERENCES
[2020-07-20 13:39:41,661 INFO  L142   InterpolantAutomaton]: Constructing interpolant automaton starting with 68 interpolants.
[2020-07-20 13:39:41,663 INFO  L144   InterpolantAutomaton]: CoverageRelationStatistics Valid=495, Invalid=4054, Unknown=7, NotChecked=0, Total=4556
[2020-07-20 13:39:41,664 INFO  L87              Difference]: Start difference. First operand 60 states and 61 transitions. Second operand 68 states.
[2020-07-20 13:39:48,062 INFO  L144             Difference]: Subtrahend was deterministic. Have not used determinization.
[2020-07-20 13:39:48,063 INFO  L93              Difference]: Finished difference Result 81 states and 86 transitions.
[2020-07-20 13:39:48,064 INFO  L141   InterpolantAutomaton]: Switched to read-only mode: deterministic interpolant automaton has 45 states. 
[2020-07-20 13:39:48,064 INFO  L78                 Accepts]: Start accepts. Automaton has 68 states. Word has length 103
[2020-07-20 13:39:48,065 INFO  L84                 Accepts]: Finished accepts. some prefix is accepted.
[2020-07-20 13:39:48,067 INFO  L225             Difference]: With dead ends: 81
[2020-07-20 13:39:48,067 INFO  L226             Difference]: Without dead ends: 75
[2020-07-20 13:39:48,070 INFO  L675         BasicCegarLoop]: 0 DeclaredPredicates, 211 GetRequests, 139 SyntacticMatches, 0 SemanticMatches, 72 ConstructedPredicates, 0 IntricatePredicates, 0 DeprecatedPredicates, 523 ImplicationChecksByTransitivity, 24.0s TimeCoverageRelationStatistics Valid=624, Invalid=4769, Unknown=9, NotChecked=0, Total=5402
[2020-07-20 13:39:48,071 INFO  L82        GeneralOperation]: Start minimizeSevpa. Operand 75 states.
[2020-07-20 13:39:48,081 INFO  L88        GeneralOperation]: Finished minimizeSevpa. Reduced states from 75 to 75.
[2020-07-20 13:39:48,082 INFO  L82        GeneralOperation]: Start removeUnreachable. Operand 75 states.
[2020-07-20 13:39:48,083 INFO  L88        GeneralOperation]: Finished removeUnreachable. Reduced from 75 states to 75 states and 76 transitions.
[2020-07-20 13:39:48,084 INFO  L78                 Accepts]: Start accepts. Automaton has 75 states and 76 transitions. Word has length 103
[2020-07-20 13:39:48,085 INFO  L84                 Accepts]: Finished accepts. word is rejected.
[2020-07-20 13:39:48,085 INFO  L479      AbstractCegarLoop]: Abstraction has 75 states and 76 transitions.
[2020-07-20 13:39:48,085 INFO  L480      AbstractCegarLoop]: Interpolant automaton has 68 states.
[2020-07-20 13:39:48,085 INFO  L276                IsEmpty]: Start isEmpty. Operand 75 states and 76 transitions.
[2020-07-20 13:39:48,090 INFO  L282                IsEmpty]: Finished isEmpty. Found accepting run of length 134
[2020-07-20 13:39:48,090 INFO  L414         BasicCegarLoop]: Found error trace
[2020-07-20 13:39:48,090 INFO  L422         BasicCegarLoop]: trace histogram [21, 21, 20, 20, 20, 20, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1]
[2020-07-20 13:39:48,296 WARN  L516      AbstractCegarLoop]: Destroyed unattended storables created during the last iteration: 6 z3 SMTLIB2_COMPLIANT=true -memory:2024 -smt2 -in
[2020-07-20 13:39:48,296 INFO  L427      AbstractCegarLoop]: === Iteration 6 === [mainErr0ASSERT_VIOLATIONERROR_FUNCTION]===
[2020-07-20 13:39:48,296 INFO  L144       PredicateUnifier]: Initialized classic predicate unifier
[2020-07-20 13:39:48,296 INFO  L82        PathProgramCache]: Analyzing trace with hash -799288067, now seen corresponding path program 5 times
[2020-07-20 13:39:48,297 INFO  L163   FreeRefinementEngine]: Executing refinement strategy FIXED_PREFERENCES
[2020-07-20 13:39:48,297 INFO  L354   FreeRefinementEngine]: Using trace check IpTcStrategyModulePreferences [873429351]
[2020-07-20 13:39:48,298 INFO  L95    rtionOrderModulation]: Keeping assertion order SMT_FEATURE_HEURISTIC (partitioning type FIXED_NUM_PARTITIONS, 4 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
[2020-07-20 13:39:53,948 INFO  L228   tOrderPrioritization]: Assert order SMT_FEATURE_HEURISTIC (partitioning type FIXED_NUM_PARTITIONS, 4 partitions) issued 4 check-sat command(s)
[2020-07-20 13:39:53,948 INFO  L229   tOrderPrioritization]: Conjunction of SSA is sat
[2020-07-20 13:39:53,949 INFO  L221             TraceCheck]: Trace is feasible, we will do another trace check, this time with branch encoders.
[2020-07-20 13:39:53,985 INFO  L136    AnnotateAndAsserter]: Conjunction of SSA is sat
[2020-07-20 13:39:53,986 INFO  L221             TraceCheck]: Trace is feasible, we will do another trace check, this time with branch encoders.
[2020-07-20 13:39:54,036 INFO  L174   FreeRefinementEngine]: Strategy FIXED_PREFERENCES found a feasible trace
[2020-07-20 13:39:54,037 INFO  L520         BasicCegarLoop]: Counterexample might be feasible
[2020-07-20 13:39:54,245 WARN  L516      AbstractCegarLoop]: Destroyed unattended storables created during the last iteration: 7 z3 SMTLIB2_COMPLIANT=true -memory:2024 -smt2 -in
[2020-07-20 13:39:54,300 INFO  L202        PluginConnector]: Adding new model de.uni_freiburg.informatik.ultimate.plugins.generator.traceabstraction CFG 20.07 01:39:54 BoogieIcfgContainer
[2020-07-20 13:39:54,300 INFO  L132        PluginConnector]: ------------------------ END TraceAbstraction----------------------------
[2020-07-20 13:39:54,303 INFO  L168              Benchmark]: Toolchain (without parser) took 85322.93 ms. Allocated memory was 143.7 MB in the beginning and 313.0 MB in the end (delta: 169.3 MB). Free memory was 101.3 MB in the beginning and 97.3 MB in the end (delta: 4.0 MB). Peak memory consumption was 173.4 MB. Max. memory is 7.1 GB.
[2020-07-20 13:39:54,304 INFO  L168              Benchmark]: CDTParser took 0.42 ms. Allocated memory is still 143.7 MB. Free memory was 119.9 MB in the beginning and 119.6 MB in the end (delta: 210.0 kB). Peak memory consumption was 210.0 kB. Max. memory is 7.1 GB.
[2020-07-20 13:39:54,304 INFO  L168              Benchmark]: CACSL2BoogieTranslator took 355.44 ms. Allocated memory is still 143.7 MB. Free memory was 100.9 MB in the beginning and 91.8 MB in the end (delta: 9.1 MB). Peak memory consumption was 9.1 MB. Max. memory is 7.1 GB.
[2020-07-20 13:39:54,305 INFO  L168              Benchmark]: Boogie Preprocessor took 42.02 ms. Allocated memory is still 143.7 MB. Free memory was 91.8 MB in the beginning and 90.4 MB in the end (delta: 1.4 MB). Peak memory consumption was 1.4 MB. Max. memory is 7.1 GB.
[2020-07-20 13:39:54,306 INFO  L168              Benchmark]: RCFGBuilder took 411.11 ms. Allocated memory was 143.7 MB in the beginning and 200.3 MB in the end (delta: 56.6 MB). Free memory was 90.4 MB in the beginning and 168.5 MB in the end (delta: -78.1 MB). Peak memory consumption was 10.0 MB. Max. memory is 7.1 GB.
[2020-07-20 13:39:54,307 INFO  L168              Benchmark]: TraceAbstraction took 84505.28 ms. Allocated memory was 200.3 MB in the beginning and 313.0 MB in the end (delta: 112.7 MB). Free memory was 167.9 MB in the beginning and 97.3 MB in the end (delta: 70.6 MB). Peak memory consumption was 183.3 MB. Max. memory is 7.1 GB.
[2020-07-20 13:39:54,311 INFO  L336   ainManager$Toolchain]: #######################  End [Toolchain 1] #######################
 --- Results ---
 * Results from de.uni_freiburg.informatik.ultimate.core:
  - StatisticsResult: Toolchain Benchmarks
    Benchmark results are:
 * CDTParser took 0.42 ms. Allocated memory is still 143.7 MB. Free memory was 119.9 MB in the beginning and 119.6 MB in the end (delta: 210.0 kB). Peak memory consumption was 210.0 kB. Max. memory is 7.1 GB.
 * CACSL2BoogieTranslator took 355.44 ms. Allocated memory is still 143.7 MB. Free memory was 100.9 MB in the beginning and 91.8 MB in the end (delta: 9.1 MB). Peak memory consumption was 9.1 MB. Max. memory is 7.1 GB.
 * Boogie Preprocessor took 42.02 ms. Allocated memory is still 143.7 MB. Free memory was 91.8 MB in the beginning and 90.4 MB in the end (delta: 1.4 MB). Peak memory consumption was 1.4 MB. Max. memory is 7.1 GB.
 * RCFGBuilder took 411.11 ms. Allocated memory was 143.7 MB in the beginning and 200.3 MB in the end (delta: 56.6 MB). Free memory was 90.4 MB in the beginning and 168.5 MB in the end (delta: -78.1 MB). Peak memory consumption was 10.0 MB. Max. memory is 7.1 GB.
 * TraceAbstraction took 84505.28 ms. Allocated memory was 200.3 MB in the beginning and 313.0 MB in the end (delta: 112.7 MB). Free memory was 167.9 MB in the beginning and 97.3 MB in the end (delta: 70.6 MB). Peak memory consumption was 183.3 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: 84.3s, OverallIterations: 6, TraceHistogramMax: 21, AutomataDifference: 42.4s, DeadEndRemovalTime: 0.0s, HoareAnnotationTime: 0.0s, InitialAbstractionConstructionTime: 0.0s, HoareTripleCheckerStatistics: 131 SDtfs, 2 SDslu, 2199 SDs, 0 SdLazy, 1098 SolverSat, 41 SolverUnsat, 2 SolverUnknown, 0 SolverNotchecked, 5.1s Time, PredicateUnifierStatistics: 0 DeclaredPredicates, 446 GetRequests, 293 SyntacticMatches, 0 SemanticMatches, 153 ConstructedPredicates, 0 IntricatePredicates, 0 DeprecatedPredicates, 720 ImplicationChecksByTransitivity, 65.4s 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, 7.1s SatisfiabilityAnalysisTime, 32.9s InterpolantComputationTime, 354 NumberOfCodeBlocks, 353 NumberOfCodeBlocksAsserted, 23 NumberOfCheckSat, 420 ConstructedInterpolants, 0 QuantifiedInterpolants, 82608 SizeOfPredicates, 5 NumberOfNonLiveVariables, 461 ConjunctsInSsa, 139 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...