./Ultimate.py --spec ../../sv-benchmarks/c/properties/unreach-call.prp --file ../../sv-benchmarks/c/hardness-nfm22/hardness_floatingpointinfluence_no-floats_file-47.i --full-output --architecture 32bit -------------------------------------------------------------------------------- Checking for ERROR reachability Using default analysis Version 9bd2c7ff Calling Ultimate with: /usr/lib/jvm/java-1.11.0-openjdk-amd64/bin/java -Dosgi.configuration.area=/tmp/vcloud_worker_vcloud-master_on_vcloud-master/run_dir_f3284760-a879-4209-91f9-daeca5ac49b2/bin/uautomizer-verify-uCwYo4JHxu/data/config -Xmx15G -Xms4m -jar /tmp/vcloud_worker_vcloud-master_on_vcloud-master/run_dir_f3284760-a879-4209-91f9-daeca5ac49b2/bin/uautomizer-verify-uCwYo4JHxu/plugins/org.eclipse.equinox.launcher_1.5.800.v20200727-1323.jar -data @noDefault -ultimatedata /tmp/vcloud_worker_vcloud-master_on_vcloud-master/run_dir_f3284760-a879-4209-91f9-daeca5ac49b2/bin/uautomizer-verify-uCwYo4JHxu/data -tc /tmp/vcloud_worker_vcloud-master_on_vcloud-master/run_dir_f3284760-a879-4209-91f9-daeca5ac49b2/bin/uautomizer-verify-uCwYo4JHxu/config/AutomizerReach.xml -i ../../sv-benchmarks/c/hardness-nfm22/hardness_floatingpointinfluence_no-floats_file-47.i -s /tmp/vcloud_worker_vcloud-master_on_vcloud-master/run_dir_f3284760-a879-4209-91f9-daeca5ac49b2/bin/uautomizer-verify-uCwYo4JHxu/config/svcomp-Reach-32bit-Automizer_Default.epf --cacsl2boogietranslator.entry.function main --witnessprinter.witness.directory /tmp/vcloud_worker_vcloud-master_on_vcloud-master/run_dir_f3284760-a879-4209-91f9-daeca5ac49b2/bin/uautomizer-verify-uCwYo4JHxu --witnessprinter.witness.filename witness --witnessprinter.write.witness.besides.input.file false --witnessprinter.graph.data.specification CHECK( init(main()), LTL(G ! call(reach_error())) ) --witnessprinter.graph.data.producer Automizer --witnessprinter.graph.data.architecture 32bit --witnessprinter.graph.data.programhash a5688f96cca39ce600e330f454e57bca5bee6291d93b987dd27f548e1ca06786 --- Real Ultimate output --- This is Ultimate 0.2.3-dev-9bd2c7f [2023-11-19 08:06:17,904 INFO L188 SettingsManager]: Resetting all preferences to default values... [2023-11-19 08:06:17,988 INFO L114 SettingsManager]: Loading settings from /tmp/vcloud_worker_vcloud-master_on_vcloud-master/run_dir_f3284760-a879-4209-91f9-daeca5ac49b2/bin/uautomizer-verify-uCwYo4JHxu/config/svcomp-Reach-32bit-Automizer_Default.epf [2023-11-19 08:06:17,993 WARN L101 SettingsManager]: Preference file contains the following unknown settings: [2023-11-19 08:06:17,994 WARN L103 SettingsManager]: * de.uni_freiburg.informatik.ultimate.core.Log level for class [2023-11-19 08:06:18,021 INFO L130 SettingsManager]: Preferences different from defaults after loading the file: [2023-11-19 08:06:18,022 INFO L151 SettingsManager]: Preferences of UltimateCore differ from their defaults: [2023-11-19 08:06:18,022 INFO L153 SettingsManager]: * Log level for class=de.uni_freiburg.informatik.ultimate.lib.smtlibutils.quantifier.QuantifierPusher=ERROR; [2023-11-19 08:06:18,023 INFO L151 SettingsManager]: Preferences of Boogie Procedure Inliner differ from their defaults: [2023-11-19 08:06:18,024 INFO L153 SettingsManager]: * Ignore calls to procedures called more than once=ONLY_FOR_SEQUENTIAL_PROGRAMS [2023-11-19 08:06:18,025 INFO L151 SettingsManager]: Preferences of BlockEncodingV2 differ from their defaults: [2023-11-19 08:06:18,025 INFO L153 SettingsManager]: * Create parallel compositions if possible=false [2023-11-19 08:06:18,026 INFO L153 SettingsManager]: * Use SBE=true [2023-11-19 08:06:18,027 INFO L151 SettingsManager]: Preferences of CACSL2BoogieTranslator differ from their defaults: [2023-11-19 08:06:18,027 INFO L153 SettingsManager]: * Pointer base address is valid at dereference=IGNORE [2023-11-19 08:06:18,028 INFO L153 SettingsManager]: * sizeof long=4 [2023-11-19 08:06:18,029 INFO L153 SettingsManager]: * Overapproximate operations on floating types=true [2023-11-19 08:06:18,029 INFO L153 SettingsManager]: * sizeof POINTER=4 [2023-11-19 08:06:18,030 INFO L153 SettingsManager]: * Check division by zero=IGNORE [2023-11-19 08:06:18,031 INFO L153 SettingsManager]: * Pointer to allocated memory at dereference=IGNORE [2023-11-19 08:06:18,031 INFO L153 SettingsManager]: * If two pointers are subtracted or compared they have the same base address=IGNORE [2023-11-19 08:06:18,032 INFO L153 SettingsManager]: * Check array bounds for arrays that are off heap=IGNORE [2023-11-19 08:06:18,033 INFO L153 SettingsManager]: * sizeof long double=12 [2023-11-19 08:06:18,033 INFO L153 SettingsManager]: * Check if freed pointer was valid=false [2023-11-19 08:06:18,034 INFO L153 SettingsManager]: * Use constant arrays=true [2023-11-19 08:06:18,035 INFO L151 SettingsManager]: Preferences of RCFGBuilder differ from their defaults: [2023-11-19 08:06:18,035 INFO L153 SettingsManager]: * Size of a code block=SequenceOfStatements [2023-11-19 08:06:18,036 INFO L153 SettingsManager]: * SMT solver=External_DefaultMode [2023-11-19 08:06:18,037 INFO L153 SettingsManager]: * Command for external solver=z3 SMTLIB2_COMPLIANT=true -memory:2024 -smt2 -in -t:2000 [2023-11-19 08:06:18,037 INFO L151 SettingsManager]: Preferences of TraceAbstraction differ from their defaults: [2023-11-19 08:06:18,038 INFO L153 SettingsManager]: * Compute Interpolants along a Counterexample=FPandBP [2023-11-19 08:06:18,038 INFO L153 SettingsManager]: * Positions where we compute the Hoare Annotation=LoopHeads [2023-11-19 08:06:18,039 INFO L153 SettingsManager]: * Trace refinement strategy=CAMEL [2023-11-19 08:06:18,039 INFO L153 SettingsManager]: * Command for external solver=z3 SMTLIB2_COMPLIANT=true -memory:2024 -smt2 -in [2023-11-19 08:06:18,040 INFO L153 SettingsManager]: * Automaton type used in concurrency analysis=PETRI_NET [2023-11-19 08:06:18,041 INFO L153 SettingsManager]: * Compute Hoare Annotation of negated interpolant automaton, abstraction and CFG=true [2023-11-19 08:06:18,041 INFO L153 SettingsManager]: * Order on configurations for Petri net unfoldings=DBO [2023-11-19 08:06:18,042 INFO L153 SettingsManager]: * SMT solver=External_ModelsAndUnsatCoreMode [2023-11-19 08:06:18,042 INFO L153 SettingsManager]: * Independence relation used for large block encoding in concurrent analysis=SYNTACTIC [2023-11-19 08:06:18,043 INFO L153 SettingsManager]: * Looper check in Petri net analysis=SEMANTIC WARNING: An illegal reflective access operation has occurred WARNING: Illegal reflective access by com.sun.xml.bind.v2.runtime.reflect.opt.Injector$1 (file:/tmp/vcloud_worker_vcloud-master_on_vcloud-master/run_dir_f3284760-a879-4209-91f9-daeca5ac49b2/bin/uautomizer-verify-uCwYo4JHxu/plugins/com.sun.xml.bind_2.2.0.v201505121915.jar) to method java.lang.ClassLoader.defineClass(java.lang.String,byte[],int,int) WARNING: Please consider reporting this to the maintainers of com.sun.xml.bind.v2.runtime.reflect.opt.Injector$1 WARNING: Use --illegal-access=warn to enable warnings of further illegal reflective access operations WARNING: All illegal access operations will be denied in a future release Applying setting for plugin de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator: Entry function -> main Applying setting for plugin de.uni_freiburg.informatik.ultimate.witnessprinter: Witness directory -> /tmp/vcloud_worker_vcloud-master_on_vcloud-master/run_dir_f3284760-a879-4209-91f9-daeca5ac49b2/bin/uautomizer-verify-uCwYo4JHxu Applying setting for plugin de.uni_freiburg.informatik.ultimate.witnessprinter: Witness filename -> witness Applying setting for plugin de.uni_freiburg.informatik.ultimate.witnessprinter: Write witness besides input file -> false Applying setting for plugin de.uni_freiburg.informatik.ultimate.witnessprinter: Graph data specification -> CHECK( init(main()), LTL(G ! call(reach_error())) ) Applying setting for plugin de.uni_freiburg.informatik.ultimate.witnessprinter: Graph data producer -> Automizer Applying setting for plugin de.uni_freiburg.informatik.ultimate.witnessprinter: Graph data architecture -> 32bit Applying setting for plugin de.uni_freiburg.informatik.ultimate.witnessprinter: Graph data programhash -> a5688f96cca39ce600e330f454e57bca5bee6291d93b987dd27f548e1ca06786 [2023-11-19 08:06:18,325 INFO L75 nceAwareModelManager]: Repository-Root is: /tmp [2023-11-19 08:06:18,358 INFO L261 ainManager$Toolchain]: [Toolchain 1]: Applicable parser(s) successfully (re)initialized [2023-11-19 08:06:18,362 INFO L217 ainManager$Toolchain]: [Toolchain 1]: Toolchain selected. [2023-11-19 08:06:18,365 INFO L270 PluginConnector]: Initializing CDTParser... [2023-11-19 08:06:18,365 INFO L274 PluginConnector]: CDTParser initialized [2023-11-19 08:06:18,367 INFO L431 ainManager$Toolchain]: [Toolchain 1]: Parsing single file: /tmp/vcloud_worker_vcloud-master_on_vcloud-master/run_dir_f3284760-a879-4209-91f9-daeca5ac49b2/bin/uautomizer-verify-uCwYo4JHxu/../../sv-benchmarks/c/hardness-nfm22/hardness_floatingpointinfluence_no-floats_file-47.i [2023-11-19 08:06:21,569 INFO L533 CDTParser]: Created temporary CDT project at NULL [2023-11-19 08:06:21,916 INFO L384 CDTParser]: Found 1 translation units. [2023-11-19 08:06:21,917 INFO L180 CDTParser]: Scanning /tmp/vcloud_worker_vcloud-master_on_vcloud-master/run_dir_f3284760-a879-4209-91f9-daeca5ac49b2/sv-benchmarks/c/hardness-nfm22/hardness_floatingpointinfluence_no-floats_file-47.i [2023-11-19 08:06:21,929 INFO L427 CDTParser]: About to delete temporary CDT project at /tmp/vcloud_worker_vcloud-master_on_vcloud-master/run_dir_f3284760-a879-4209-91f9-daeca5ac49b2/bin/uautomizer-verify-uCwYo4JHxu/data/c27e19f2d/b6aea93cf6894ad891d59752a16f73e6/FLAGa3b600c07 [2023-11-19 08:06:21,947 INFO L435 CDTParser]: Successfully deleted /tmp/vcloud_worker_vcloud-master_on_vcloud-master/run_dir_f3284760-a879-4209-91f9-daeca5ac49b2/bin/uautomizer-verify-uCwYo4JHxu/data/c27e19f2d/b6aea93cf6894ad891d59752a16f73e6 [2023-11-19 08:06:21,953 INFO L299 ainManager$Toolchain]: ####################### [Toolchain 1] ####################### [2023-11-19 08:06:21,955 INFO L133 ToolchainWalker]: Walking toolchain with 6 elements. [2023-11-19 08:06:21,957 INFO L112 PluginConnector]: ------------------------CACSL2BoogieTranslator---------------------------- [2023-11-19 08:06:21,958 INFO L270 PluginConnector]: Initializing CACSL2BoogieTranslator... [2023-11-19 08:06:21,963 INFO L274 PluginConnector]: CACSL2BoogieTranslator initialized [2023-11-19 08:06:21,965 INFO L184 PluginConnector]: Executing the observer ACSLObjectContainerObserver from plugin CACSL2BoogieTranslator for "CDTParser AST 19.11 08:06:21" (1/1) ... [2023-11-19 08:06:21,967 INFO L204 PluginConnector]: Invalid model from CACSL2BoogieTranslator for observer de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator.ACSLObjectContainerObserver@3aced033 and model type de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 19.11 08:06:21, skipping insertion in model container [2023-11-19 08:06:21,967 INFO L184 PluginConnector]: Executing the observer CACSL2BoogieTranslatorObserver from plugin CACSL2BoogieTranslator for "CDTParser AST 19.11 08:06:21" (1/1) ... [2023-11-19 08:06:22,003 INFO L177 MainTranslator]: Built tables and reachable declarations [2023-11-19 08:06:22,146 WARN L240 ndardFunctionHandler]: Function reach_error is already implemented but we override the implementation for the call at /tmp/vcloud_worker_vcloud-master_on_vcloud-master/run_dir_f3284760-a879-4209-91f9-daeca5ac49b2/sv-benchmarks/c/hardness-nfm22/hardness_floatingpointinfluence_no-floats_file-47.i[916,929] [2023-11-19 08:06:22,197 INFO L209 PostProcessor]: Analyzing one entry point: main [2023-11-19 08:06:22,206 INFO L202 MainTranslator]: Completed pre-run [2023-11-19 08:06:22,217 WARN L240 ndardFunctionHandler]: Function reach_error is already implemented but we override the implementation for the call at /tmp/vcloud_worker_vcloud-master_on_vcloud-master/run_dir_f3284760-a879-4209-91f9-daeca5ac49b2/sv-benchmarks/c/hardness-nfm22/hardness_floatingpointinfluence_no-floats_file-47.i[916,929] [2023-11-19 08:06:22,245 INFO L209 PostProcessor]: Analyzing one entry point: main [2023-11-19 08:06:22,260 INFO L206 MainTranslator]: Completed translation [2023-11-19 08:06:22,261 INFO L201 PluginConnector]: Adding new model de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 19.11 08:06:22 WrapperNode [2023-11-19 08:06:22,261 INFO L131 PluginConnector]: ------------------------ END CACSL2BoogieTranslator---------------------------- [2023-11-19 08:06:22,262 INFO L112 PluginConnector]: ------------------------Boogie Procedure Inliner---------------------------- [2023-11-19 08:06:22,262 INFO L270 PluginConnector]: Initializing Boogie Procedure Inliner... [2023-11-19 08:06:22,263 INFO L274 PluginConnector]: Boogie Procedure Inliner initialized [2023-11-19 08:06:22,270 INFO L184 PluginConnector]: Executing the observer TypeChecker from plugin Boogie Procedure Inliner for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 19.11 08:06:22" (1/1) ... [2023-11-19 08:06:22,277 INFO L184 PluginConnector]: Executing the observer Inliner from plugin Boogie Procedure Inliner for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 19.11 08:06:22" (1/1) ... [2023-11-19 08:06:22,301 INFO L138 Inliner]: procedures = 26, calls = 23, calls flagged for inlining = 8, calls inlined = 8, statements flattened = 88 [2023-11-19 08:06:22,301 INFO L131 PluginConnector]: ------------------------ END Boogie Procedure Inliner---------------------------- [2023-11-19 08:06:22,302 INFO L112 PluginConnector]: ------------------------Boogie Preprocessor---------------------------- [2023-11-19 08:06:22,302 INFO L270 PluginConnector]: Initializing Boogie Preprocessor... [2023-11-19 08:06:22,302 INFO L274 PluginConnector]: Boogie Preprocessor initialized [2023-11-19 08:06:22,311 INFO L184 PluginConnector]: Executing the observer EnsureBoogieModelObserver from plugin Boogie Preprocessor for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 19.11 08:06:22" (1/1) ... [2023-11-19 08:06:22,312 INFO L184 PluginConnector]: Executing the observer TypeChecker from plugin Boogie Preprocessor for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 19.11 08:06:22" (1/1) ... [2023-11-19 08:06:22,314 INFO L184 PluginConnector]: Executing the observer ConstExpander from plugin Boogie Preprocessor for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 19.11 08:06:22" (1/1) ... [2023-11-19 08:06:22,314 INFO L184 PluginConnector]: Executing the observer StructExpander from plugin Boogie Preprocessor for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 19.11 08:06:22" (1/1) ... [2023-11-19 08:06:22,319 INFO L184 PluginConnector]: Executing the observer UnstructureCode from plugin Boogie Preprocessor for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 19.11 08:06:22" (1/1) ... [2023-11-19 08:06:22,322 INFO L184 PluginConnector]: Executing the observer FunctionInliner from plugin Boogie Preprocessor for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 19.11 08:06:22" (1/1) ... [2023-11-19 08:06:22,324 INFO L184 PluginConnector]: Executing the observer LTLStepAnnotator from plugin Boogie Preprocessor for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 19.11 08:06:22" (1/1) ... [2023-11-19 08:06:22,325 INFO L184 PluginConnector]: Executing the observer BoogieSymbolTableConstructor from plugin Boogie Preprocessor for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 19.11 08:06:22" (1/1) ... [2023-11-19 08:06:22,328 INFO L131 PluginConnector]: ------------------------ END Boogie Preprocessor---------------------------- [2023-11-19 08:06:22,329 INFO L112 PluginConnector]: ------------------------RCFGBuilder---------------------------- [2023-11-19 08:06:22,329 INFO L270 PluginConnector]: Initializing RCFGBuilder... [2023-11-19 08:06:22,329 INFO L274 PluginConnector]: RCFGBuilder initialized [2023-11-19 08:06:22,330 INFO L184 PluginConnector]: Executing the observer RCFGBuilderObserver from plugin RCFGBuilder for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 19.11 08:06:22" (1/1) ... [2023-11-19 08:06:22,341 INFO L173 SolverBuilder]: Constructing external solver with command: z3 SMTLIB2_COMPLIANT=true -memory:2024 -smt2 -in -t:2000 [2023-11-19 08:06:22,360 INFO L189 MonitoredProcess]: No working directory specified, using /tmp/vcloud_worker_vcloud-master_on_vcloud-master/run_dir_f3284760-a879-4209-91f9-daeca5ac49b2/bin/uautomizer-verify-uCwYo4JHxu/z3 [2023-11-19 08:06:22,387 INFO L229 MonitoredProcess]: Starting monitored process 1 with /tmp/vcloud_worker_vcloud-master_on_vcloud-master/run_dir_f3284760-a879-4209-91f9-daeca5ac49b2/bin/uautomizer-verify-uCwYo4JHxu/z3 SMTLIB2_COMPLIANT=true -memory:2024 -smt2 -in -t:2000 (exit command is (exit), workingDir is null) [2023-11-19 08:06:22,392 INFO L327 MonitoredProcess]: [MP /tmp/vcloud_worker_vcloud-master_on_vcloud-master/run_dir_f3284760-a879-4209-91f9-daeca5ac49b2/bin/uautomizer-verify-uCwYo4JHxu/z3 SMTLIB2_COMPLIANT=true -memory:2024 -smt2 -in -t:2000 (1)] Waiting until timeout for monitored process [2023-11-19 08:06:22,415 INFO L130 BoogieDeclarations]: Found specification of procedure #Ultimate.allocInit [2023-11-19 08:06:22,415 INFO L130 BoogieDeclarations]: Found specification of procedure assume_abort_if_not [2023-11-19 08:06:22,416 INFO L138 BoogieDeclarations]: Found implementation of procedure assume_abort_if_not [2023-11-19 08:06:22,416 INFO L130 BoogieDeclarations]: Found specification of procedure write~init~int [2023-11-19 08:06:22,416 INFO L130 BoogieDeclarations]: Found specification of procedure ULTIMATE.start [2023-11-19 08:06:22,416 INFO L138 BoogieDeclarations]: Found implementation of procedure ULTIMATE.start [2023-11-19 08:06:22,484 INFO L236 CfgBuilder]: Building ICFG [2023-11-19 08:06:22,485 INFO L262 CfgBuilder]: Building CFG for each procedure with an implementation [2023-11-19 08:06:22,669 INFO L277 CfgBuilder]: Performing block encoding [2023-11-19 08:06:22,677 INFO L297 CfgBuilder]: Using the 1 location(s) as analysis (start of procedure ULTIMATE.start) [2023-11-19 08:06:22,677 INFO L302 CfgBuilder]: Removed 1 assume(true) statements. [2023-11-19 08:06:22,681 INFO L201 PluginConnector]: Adding new model de.uni_freiburg.informatik.ultimate.plugins.generator.rcfgbuilder CFG 19.11 08:06:22 BoogieIcfgContainer [2023-11-19 08:06:22,681 INFO L131 PluginConnector]: ------------------------ END RCFGBuilder---------------------------- [2023-11-19 08:06:22,683 INFO L112 PluginConnector]: ------------------------TraceAbstraction---------------------------- [2023-11-19 08:06:22,684 INFO L270 PluginConnector]: Initializing TraceAbstraction... [2023-11-19 08:06:22,687 INFO L274 PluginConnector]: TraceAbstraction initialized [2023-11-19 08:06:22,687 INFO L184 PluginConnector]: Executing the observer TraceAbstractionObserver from plugin TraceAbstraction for "CDTParser AST 19.11 08:06:21" (1/3) ... [2023-11-19 08:06:22,688 INFO L204 PluginConnector]: Invalid model from TraceAbstraction for observer de.uni_freiburg.informatik.ultimate.plugins.generator.traceabstraction.TraceAbstractionObserver@700293 and model type de.uni_freiburg.informatik.ultimate.plugins.generator.traceabstraction AST 19.11 08:06:22, skipping insertion in model container [2023-11-19 08:06:22,688 INFO L184 PluginConnector]: Executing the observer TraceAbstractionObserver from plugin TraceAbstraction for "de.uni_freiburg.informatik.ultimate.plugins.generator.cacsl2boogietranslator AST 19.11 08:06:22" (2/3) ... [2023-11-19 08:06:22,688 INFO L204 PluginConnector]: Invalid model from TraceAbstraction for observer de.uni_freiburg.informatik.ultimate.plugins.generator.traceabstraction.TraceAbstractionObserver@700293 and model type de.uni_freiburg.informatik.ultimate.plugins.generator.traceabstraction AST 19.11 08:06:22, skipping insertion in model container [2023-11-19 08:06:22,689 INFO L184 PluginConnector]: Executing the observer TraceAbstractionObserver from plugin TraceAbstraction for "de.uni_freiburg.informatik.ultimate.plugins.generator.rcfgbuilder CFG 19.11 08:06:22" (3/3) ... [2023-11-19 08:06:22,690 INFO L112 eAbstractionObserver]: Analyzing ICFG hardness_floatingpointinfluence_no-floats_file-47.i [2023-11-19 08:06:22,709 INFO L203 ceAbstractionStarter]: Automizer settings: Hoare:true NWA Interpolation:FPandBP Determinization: PREDICATE_ABSTRACTION [2023-11-19 08:06:22,710 INFO L162 ceAbstractionStarter]: Applying trace abstraction to program that has 1 error locations. [2023-11-19 08:06:22,769 INFO L356 AbstractCegarLoop]: ======== Iteration 0 == of CEGAR loop == AllErrorsAtOnce ======== [2023-11-19 08:06:22,776 INFO L357 AbstractCegarLoop]: Settings: SEPARATE_VIOLATION_CHECK=true, mInterprocedural=true, mMaxIterations=1000000, mWatchIteration=1000000, mArtifact=RCFG, mInterpolation=FPandBP, mInterpolantAutomaton=STRAIGHT_LINE, mDumpAutomata=false, mAutomataFormat=ATS_NUMERATE, mDumpPath=., mDeterminiation=PREDICATE_ABSTRACTION, mMinimize=MINIMIZE_SEVPA, mHoare=true, mAutomataTypeConcurrency=PETRI_NET, mHoareTripleChecks=INCREMENTAL, mHoareAnnotationPositions=LoopHeads, mDumpOnlyReuseAutomata=false, mLimitTraceHistogram=0, mErrorLocTimeLimit=0, mLimitPathProgramCount=0, mCollectInterpolantStatistics=true, mHeuristicEmptinessCheck=false, mHeuristicEmptinessCheckAStarHeuristic=ZERO, mHeuristicEmptinessCheckAStarHeuristicRandomSeed=1337, mHeuristicEmptinessCheckSmtFeatureScoringMethod=DAGSIZE, mSMTFeatureExtraction=false, mSMTFeatureExtractionDumpPath=., mOverrideInterpolantAutomaton=false, mMcrInterpolantMethod=WP, mPorIndependenceSettings=[Lde.uni_freiburg.informatik.ultimate.lib.tracecheckerutils.partialorder.independence.IndependenceSettings;@35a26eaa, mLbeIndependenceSettings=[IndependenceType=SYNTACTIC, AbstractionType=NONE, UseConditional=, UseSemiCommutativity=, Solver=, SolverTimeout=] [2023-11-19 08:06:22,776 INFO L358 AbstractCegarLoop]: Starting to check reachability of 1 error locations. [2023-11-19 08:06:22,781 INFO L276 IsEmpty]: Start isEmpty. Operand has 43 states, 30 states have (on average 1.4) internal successors, (42), 31 states have internal predecessors, (42), 10 states have call successors, (10), 1 states have call predecessors, (10), 1 states have return successors, (10), 10 states have call predecessors, (10), 10 states have call successors, (10) [2023-11-19 08:06:22,792 INFO L282 IsEmpty]: Finished isEmpty. Found accepting run of length 71 [2023-11-19 08:06:22,792 INFO L187 NwaCegarLoop]: Found error trace [2023-11-19 08:06:22,793 INFO L195 NwaCegarLoop]: trace histogram [10, 10, 10, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1] [2023-11-19 08:06:22,794 INFO L420 AbstractCegarLoop]: === Iteration 1 === Targeting ULTIMATE.startErr0ASSERT_VIOLATIONERROR_FUNCTION === [ULTIMATE.startErr0ASSERT_VIOLATIONERROR_FUNCTION] === [2023-11-19 08:06:22,799 INFO L160 PredicateUnifier]: Initialized classic predicate unifier [2023-11-19 08:06:22,799 INFO L85 PathProgramCache]: Analyzing trace with hash 920331229, now seen corresponding path program 1 times [2023-11-19 08:06:22,808 INFO L118 FreeRefinementEngine]: Executing refinement strategy CAMEL [2023-11-19 08:06:22,809 INFO L334 FreeRefinementEngine]: Using trace check IpTcStrategyModuleSmtInterpolCraig [1586735503] [2023-11-19 08:06:22,809 INFO L95 rtionOrderModulation]: Keeping assertion order NOT_INCREMENTALLY [2023-11-19 08:06:22,811 INFO L127 SolverBuilder]: Constructing new instance of SMTInterpol with explicit timeout -1 ms and remaining time -1 ms [2023-11-19 08:06:22,936 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2023-11-19 08:06:23,033 INFO L376 atingTraceCheckCraig]: Compute interpolants for subsequence at non-pending call position 5 [2023-11-19 08:06:23,041 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2023-11-19 08:06:23,047 INFO L376 atingTraceCheckCraig]: Compute interpolants for subsequence at non-pending call position 10 [2023-11-19 08:06:23,050 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2023-11-19 08:06:23,054 INFO L376 atingTraceCheckCraig]: Compute interpolants for subsequence at non-pending call position 16 [2023-11-19 08:06:23,057 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2023-11-19 08:06:23,061 INFO L376 atingTraceCheckCraig]: Compute interpolants for subsequence at non-pending call position 21 [2023-11-19 08:06:23,064 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2023-11-19 08:06:23,070 INFO L376 atingTraceCheckCraig]: Compute interpolants for subsequence at non-pending call position 27 [2023-11-19 08:06:23,073 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2023-11-19 08:06:23,078 INFO L376 atingTraceCheckCraig]: Compute interpolants for subsequence at non-pending call position 32 [2023-11-19 08:06:23,082 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2023-11-19 08:06:23,086 INFO L376 atingTraceCheckCraig]: Compute interpolants for subsequence at non-pending call position 38 [2023-11-19 08:06:23,103 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2023-11-19 08:06:23,106 INFO L376 atingTraceCheckCraig]: Compute interpolants for subsequence at non-pending call position 43 [2023-11-19 08:06:23,110 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2023-11-19 08:06:23,115 INFO L376 atingTraceCheckCraig]: Compute interpolants for subsequence at non-pending call position 49 [2023-11-19 08:06:23,118 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2023-11-19 08:06:23,122 INFO L376 atingTraceCheckCraig]: Compute interpolants for subsequence at non-pending call position 54 [2023-11-19 08:06:23,124 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2023-11-19 08:06:23,130 INFO L134 CoverageAnalysis]: Checked inductivity of 180 backedges. 0 proven. 0 refuted. 0 times theorem prover too weak. 180 trivial. 0 not checked. [2023-11-19 08:06:23,130 INFO L136 FreeRefinementEngine]: Strategy CAMEL found an infeasible trace [2023-11-19 08:06:23,131 INFO L334 FreeRefinementEngine]: Using interpolant generator IpTcStrategyModuleSmtInterpolCraig [1586735503] [2023-11-19 08:06:23,132 INFO L158 FreeRefinementEngine]: IpTcStrategyModuleSmtInterpolCraig [1586735503] provided 1 perfect and 0 imperfect interpolant sequences [2023-11-19 08:06:23,132 INFO L185 FreeRefinementEngine]: Found 1 perfect and 0 imperfect interpolant sequences. [2023-11-19 08:06:23,132 INFO L198 FreeRefinementEngine]: Number of different interpolants: perfect sequences [2] imperfect sequences [] total 2 [2023-11-19 08:06:23,134 INFO L121 tionRefinementEngine]: Using interpolant automaton builder IpAbStrategyModuleStraightlineAll [685687877] [2023-11-19 08:06:23,135 INFO L85 oduleStraightlineAll]: Using 1 perfect interpolants to construct interpolant automaton [2023-11-19 08:06:23,140 INFO L571 AbstractCegarLoop]: INTERPOLANT automaton has 2 states [2023-11-19 08:06:23,140 INFO L100 FreeRefinementEngine]: Using predicate unifier PredicateUnifier provided by strategy CAMEL [2023-11-19 08:06:23,184 INFO L143 InterpolantAutomaton]: Constructing interpolant automaton starting with 2 interpolants. [2023-11-19 08:06:23,185 INFO L145 InterpolantAutomaton]: CoverageRelationStatistics Valid=1, Invalid=1, Unknown=0, NotChecked=0, Total=2 [2023-11-19 08:06:23,187 INFO L87 Difference]: Start difference. First operand has 43 states, 30 states have (on average 1.4) internal successors, (42), 31 states have internal predecessors, (42), 10 states have call successors, (10), 1 states have call predecessors, (10), 1 states have return successors, (10), 10 states have call predecessors, (10), 10 states have call successors, (10) Second operand has 2 states, 2 states have (on average 11.5) internal successors, (23), 2 states have internal predecessors, (23), 2 states have call successors, (10), 1 states have call predecessors, (10), 1 states have return successors, (10), 1 states have call predecessors, (10), 2 states have call successors, (10) [2023-11-19 08:06:23,230 INFO L144 Difference]: Subtrahend was deterministic. Have not used determinization. [2023-11-19 08:06:23,231 INFO L93 Difference]: Finished difference Result 78 states and 126 transitions. [2023-11-19 08:06:23,232 INFO L141 InterpolantAutomaton]: Switched to read-only mode: deterministic interpolant automaton has 2 states. [2023-11-19 08:06:23,233 INFO L78 Accepts]: Start accepts. Automaton has has 2 states, 2 states have (on average 11.5) internal successors, (23), 2 states have internal predecessors, (23), 2 states have call successors, (10), 1 states have call predecessors, (10), 1 states have return successors, (10), 1 states have call predecessors, (10), 2 states have call successors, (10) Word has length 70 [2023-11-19 08:06:23,234 INFO L84 Accepts]: Finished accepts. some prefix is accepted. [2023-11-19 08:06:23,241 INFO L225 Difference]: With dead ends: 78 [2023-11-19 08:06:23,242 INFO L226 Difference]: Without dead ends: 38 [2023-11-19 08:06:23,245 INFO L412 NwaCegarLoop]: 0 DeclaredPredicates, 32 GetRequests, 32 SyntacticMatches, 0 SemanticMatches, 0 ConstructedPredicates, 0 IntricatePredicates, 0 DeprecatedPredicates, 0 ImplicationChecksByTransitivity, 0.0s TimeCoverageRelationStatistics Valid=1, Invalid=1, Unknown=0, NotChecked=0, Total=2 [2023-11-19 08:06:23,249 INFO L413 NwaCegarLoop]: 52 mSDtfsCounter, 0 mSDsluCounter, 0 mSDsCounter, 0 mSdLazyCounter, 0 mSolverCounterSat, 0 mSolverCounterUnsat, 0 mSolverCounterUnknown, 0 mSolverCounterNotChecked, 0.0s Time, 0 mProtectedPredicate, 0 mProtectedAction, 0 SdHoareTripleChecker+Valid, 52 SdHoareTripleChecker+Invalid, 0 SdHoareTripleChecker+Unknown, 0 SdHoareTripleChecker+Unchecked, 0.0s SdHoareTripleChecker+Time, 0 IncrementalHoareTripleChecker+Valid, 0 IncrementalHoareTripleChecker+Invalid, 0 IncrementalHoareTripleChecker+Unknown, 0 IncrementalHoareTripleChecker+Unchecked, 0.0s IncrementalHoareTripleChecker+Time [2023-11-19 08:06:23,250 INFO L414 NwaCegarLoop]: SdHoareTripleChecker [0 Valid, 52 Invalid, 0 Unknown, 0 Unchecked, 0.0s Time], IncrementalHoareTripleChecker [0 Valid, 0 Invalid, 0 Unknown, 0 Unchecked, 0.0s Time] [2023-11-19 08:06:23,267 INFO L82 GeneralOperation]: Start minimizeSevpa. Operand 38 states. [2023-11-19 08:06:23,294 INFO L88 GeneralOperation]: Finished minimizeSevpa. Reduced states from 38 to 38. [2023-11-19 08:06:23,295 INFO L82 GeneralOperation]: Start removeUnreachable. Operand has 38 states, 26 states have (on average 1.2307692307692308) internal successors, (32), 26 states have internal predecessors, (32), 10 states have call successors, (10), 1 states have call predecessors, (10), 1 states have return successors, (10), 10 states have call predecessors, (10), 10 states have call successors, (10) [2023-11-19 08:06:23,297 INFO L88 GeneralOperation]: Finished removeUnreachable. Reduced from 38 states to 38 states and 52 transitions. [2023-11-19 08:06:23,299 INFO L78 Accepts]: Start accepts. Automaton has 38 states and 52 transitions. Word has length 70 [2023-11-19 08:06:23,299 INFO L84 Accepts]: Finished accepts. word is rejected. [2023-11-19 08:06:23,299 INFO L495 AbstractCegarLoop]: Abstraction has 38 states and 52 transitions. [2023-11-19 08:06:23,300 INFO L496 AbstractCegarLoop]: INTERPOLANT automaton has has 2 states, 2 states have (on average 11.5) internal successors, (23), 2 states have internal predecessors, (23), 2 states have call successors, (10), 1 states have call predecessors, (10), 1 states have return successors, (10), 1 states have call predecessors, (10), 2 states have call successors, (10) [2023-11-19 08:06:23,300 INFO L276 IsEmpty]: Start isEmpty. Operand 38 states and 52 transitions. [2023-11-19 08:06:23,304 INFO L282 IsEmpty]: Finished isEmpty. Found accepting run of length 71 [2023-11-19 08:06:23,304 INFO L187 NwaCegarLoop]: Found error trace [2023-11-19 08:06:23,304 INFO L195 NwaCegarLoop]: trace histogram [10, 10, 10, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1] [2023-11-19 08:06:23,304 WARN L477 AbstractCegarLoop]: Destroyed unattended storables created during the last iteration: SelfDestructingSolverStorable0 [2023-11-19 08:06:23,305 INFO L420 AbstractCegarLoop]: === Iteration 2 === Targeting ULTIMATE.startErr0ASSERT_VIOLATIONERROR_FUNCTION === [ULTIMATE.startErr0ASSERT_VIOLATIONERROR_FUNCTION] === [2023-11-19 08:06:23,305 INFO L160 PredicateUnifier]: Initialized classic predicate unifier [2023-11-19 08:06:23,306 INFO L85 PathProgramCache]: Analyzing trace with hash -620259169, now seen corresponding path program 1 times [2023-11-19 08:06:23,306 INFO L118 FreeRefinementEngine]: Executing refinement strategy CAMEL [2023-11-19 08:06:23,306 INFO L334 FreeRefinementEngine]: Using trace check IpTcStrategyModuleSmtInterpolCraig [1586203231] [2023-11-19 08:06:23,306 INFO L95 rtionOrderModulation]: Keeping assertion order NOT_INCREMENTALLY [2023-11-19 08:06:23,307 INFO L127 SolverBuilder]: Constructing new instance of SMTInterpol with explicit timeout -1 ms and remaining time -1 ms [2023-11-19 08:06:23,384 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2023-11-19 08:07:18,472 INFO L376 atingTraceCheckCraig]: Compute interpolants for subsequence at non-pending call position 5 [2023-11-19 08:07:18,474 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2023-11-19 08:07:18,478 INFO L376 atingTraceCheckCraig]: Compute interpolants for subsequence at non-pending call position 10 [2023-11-19 08:07:18,479 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2023-11-19 08:07:18,481 INFO L376 atingTraceCheckCraig]: Compute interpolants for subsequence at non-pending call position 16 [2023-11-19 08:07:18,483 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2023-11-19 08:07:18,484 INFO L376 atingTraceCheckCraig]: Compute interpolants for subsequence at non-pending call position 21 [2023-11-19 08:07:18,486 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2023-11-19 08:07:18,488 INFO L376 atingTraceCheckCraig]: Compute interpolants for subsequence at non-pending call position 27 [2023-11-19 08:07:18,490 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2023-11-19 08:07:18,491 INFO L376 atingTraceCheckCraig]: Compute interpolants for subsequence at non-pending call position 32 [2023-11-19 08:07:18,493 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2023-11-19 08:07:18,495 INFO L376 atingTraceCheckCraig]: Compute interpolants for subsequence at non-pending call position 38 [2023-11-19 08:07:18,496 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2023-11-19 08:07:18,498 INFO L376 atingTraceCheckCraig]: Compute interpolants for subsequence at non-pending call position 43 [2023-11-19 08:07:18,499 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2023-11-19 08:07:18,502 INFO L376 atingTraceCheckCraig]: Compute interpolants for subsequence at non-pending call position 49 [2023-11-19 08:07:18,503 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2023-11-19 08:07:18,505 INFO L376 atingTraceCheckCraig]: Compute interpolants for subsequence at non-pending call position 54 [2023-11-19 08:07:18,506 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2023-11-19 08:07:18,508 INFO L134 CoverageAnalysis]: Checked inductivity of 180 backedges. 0 proven. 0 refuted. 0 times theorem prover too weak. 180 trivial. 0 not checked. [2023-11-19 08:07:18,509 INFO L136 FreeRefinementEngine]: Strategy CAMEL found an infeasible trace [2023-11-19 08:07:18,509 INFO L334 FreeRefinementEngine]: Using interpolant generator IpTcStrategyModuleSmtInterpolCraig [1586203231] [2023-11-19 08:07:18,509 INFO L158 FreeRefinementEngine]: IpTcStrategyModuleSmtInterpolCraig [1586203231] provided 1 perfect and 0 imperfect interpolant sequences [2023-11-19 08:07:18,509 INFO L185 FreeRefinementEngine]: Found 1 perfect and 0 imperfect interpolant sequences. [2023-11-19 08:07:18,510 INFO L198 FreeRefinementEngine]: Number of different interpolants: perfect sequences [9] imperfect sequences [] total 9 [2023-11-19 08:07:18,510 INFO L121 tionRefinementEngine]: Using interpolant automaton builder IpAbStrategyModuleStraightlineAll [1732112593] [2023-11-19 08:07:18,510 INFO L85 oduleStraightlineAll]: Using 1 perfect interpolants to construct interpolant automaton [2023-11-19 08:07:18,511 INFO L571 AbstractCegarLoop]: INTERPOLANT automaton has 9 states [2023-11-19 08:07:18,512 INFO L100 FreeRefinementEngine]: Using predicate unifier PredicateUnifier provided by strategy CAMEL [2023-11-19 08:07:18,512 INFO L143 InterpolantAutomaton]: Constructing interpolant automaton starting with 9 interpolants. [2023-11-19 08:07:18,513 INFO L145 InterpolantAutomaton]: CoverageRelationStatistics Valid=21, Invalid=51, Unknown=0, NotChecked=0, Total=72 [2023-11-19 08:07:18,513 INFO L87 Difference]: Start difference. First operand 38 states and 52 transitions. Second operand has 9 states, 9 states have (on average 2.5555555555555554) internal successors, (23), 9 states have internal predecessors, (23), 1 states have call successors, (10), 1 states have call predecessors, (10), 1 states have return successors, (10), 1 states have call predecessors, (10), 1 states have call successors, (10) [2023-11-19 08:07:19,326 INFO L144 Difference]: Subtrahend was deterministic. Have not used determinization. [2023-11-19 08:07:19,327 INFO L93 Difference]: Finished difference Result 99 states and 136 transitions. [2023-11-19 08:07:19,327 INFO L141 InterpolantAutomaton]: Switched to read-only mode: deterministic interpolant automaton has 17 states. [2023-11-19 08:07:19,327 INFO L78 Accepts]: Start accepts. Automaton has has 9 states, 9 states have (on average 2.5555555555555554) internal successors, (23), 9 states have internal predecessors, (23), 1 states have call successors, (10), 1 states have call predecessors, (10), 1 states have return successors, (10), 1 states have call predecessors, (10), 1 states have call successors, (10) Word has length 70 [2023-11-19 08:07:19,328 INFO L84 Accepts]: Finished accepts. some prefix is accepted. [2023-11-19 08:07:19,331 INFO L225 Difference]: With dead ends: 99 [2023-11-19 08:07:19,331 INFO L226 Difference]: Without dead ends: 97 [2023-11-19 08:07:19,332 INFO L412 NwaCegarLoop]: 0 DeclaredPredicates, 41 GetRequests, 22 SyntacticMatches, 0 SemanticMatches, 19 ConstructedPredicates, 0 IntricatePredicates, 0 DeprecatedPredicates, 59 ImplicationChecksByTransitivity, 0.6s TimeCoverageRelationStatistics Valid=126, Invalid=294, Unknown=0, NotChecked=0, Total=420 [2023-11-19 08:07:19,334 INFO L413 NwaCegarLoop]: 71 mSDtfsCounter, 63 mSDsluCounter, 242 mSDsCounter, 0 mSdLazyCounter, 188 mSolverCounterSat, 5 mSolverCounterUnsat, 0 mSolverCounterUnknown, 0 mSolverCounterNotChecked, 0.2s Time, 0 mProtectedPredicate, 0 mProtectedAction, 73 SdHoareTripleChecker+Valid, 313 SdHoareTripleChecker+Invalid, 193 SdHoareTripleChecker+Unknown, 0 SdHoareTripleChecker+Unchecked, 0.0s SdHoareTripleChecker+Time, 5 IncrementalHoareTripleChecker+Valid, 188 IncrementalHoareTripleChecker+Invalid, 0 IncrementalHoareTripleChecker+Unknown, 0 IncrementalHoareTripleChecker+Unchecked, 0.3s IncrementalHoareTripleChecker+Time [2023-11-19 08:07:19,334 INFO L414 NwaCegarLoop]: SdHoareTripleChecker [73 Valid, 313 Invalid, 193 Unknown, 0 Unchecked, 0.0s Time], IncrementalHoareTripleChecker [5 Valid, 188 Invalid, 0 Unknown, 0 Unchecked, 0.3s Time] [2023-11-19 08:07:19,336 INFO L82 GeneralOperation]: Start minimizeSevpa. Operand 97 states. [2023-11-19 08:07:19,347 INFO L88 GeneralOperation]: Finished minimizeSevpa. Reduced states from 97 to 46. [2023-11-19 08:07:19,347 INFO L82 GeneralOperation]: Start removeUnreachable. Operand has 46 states, 34 states have (on average 1.2352941176470589) internal successors, (42), 34 states have internal predecessors, (42), 10 states have call successors, (10), 1 states have call predecessors, (10), 1 states have return successors, (10), 10 states have call predecessors, (10), 10 states have call successors, (10) [2023-11-19 08:07:19,348 INFO L88 GeneralOperation]: Finished removeUnreachable. Reduced from 46 states to 46 states and 62 transitions. [2023-11-19 08:07:19,349 INFO L78 Accepts]: Start accepts. Automaton has 46 states and 62 transitions. Word has length 70 [2023-11-19 08:07:19,349 INFO L84 Accepts]: Finished accepts. word is rejected. [2023-11-19 08:07:19,350 INFO L495 AbstractCegarLoop]: Abstraction has 46 states and 62 transitions. [2023-11-19 08:07:19,350 INFO L496 AbstractCegarLoop]: INTERPOLANT automaton has has 9 states, 9 states have (on average 2.5555555555555554) internal successors, (23), 9 states have internal predecessors, (23), 1 states have call successors, (10), 1 states have call predecessors, (10), 1 states have return successors, (10), 1 states have call predecessors, (10), 1 states have call successors, (10) [2023-11-19 08:07:19,350 INFO L276 IsEmpty]: Start isEmpty. Operand 46 states and 62 transitions. [2023-11-19 08:07:19,353 INFO L282 IsEmpty]: Finished isEmpty. Found accepting run of length 72 [2023-11-19 08:07:19,353 INFO L187 NwaCegarLoop]: Found error trace [2023-11-19 08:07:19,353 INFO L195 NwaCegarLoop]: trace histogram [10, 10, 10, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1] [2023-11-19 08:07:19,354 WARN L477 AbstractCegarLoop]: Destroyed unattended storables created during the last iteration: SelfDestructingSolverStorable1 [2023-11-19 08:07:19,354 INFO L420 AbstractCegarLoop]: === Iteration 3 === Targeting ULTIMATE.startErr0ASSERT_VIOLATIONERROR_FUNCTION === [ULTIMATE.startErr0ASSERT_VIOLATIONERROR_FUNCTION] === [2023-11-19 08:07:19,354 INFO L160 PredicateUnifier]: Initialized classic predicate unifier [2023-11-19 08:07:19,355 INFO L85 PathProgramCache]: Analyzing trace with hash 1514660546, now seen corresponding path program 1 times [2023-11-19 08:07:19,355 INFO L118 FreeRefinementEngine]: Executing refinement strategy CAMEL [2023-11-19 08:07:19,355 INFO L334 FreeRefinementEngine]: Using trace check IpTcStrategyModuleSmtInterpolCraig [1766218871] [2023-11-19 08:07:19,355 INFO L95 rtionOrderModulation]: Keeping assertion order NOT_INCREMENTALLY [2023-11-19 08:07:19,356 INFO L127 SolverBuilder]: Constructing new instance of SMTInterpol with explicit timeout -1 ms and remaining time -1 ms [2023-11-19 08:07:19,375 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2023-11-19 08:07:19,431 INFO L376 atingTraceCheckCraig]: Compute interpolants for subsequence at non-pending call position 5 [2023-11-19 08:07:19,433 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2023-11-19 08:07:19,436 INFO L376 atingTraceCheckCraig]: Compute interpolants for subsequence at non-pending call position 10 [2023-11-19 08:07:19,438 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2023-11-19 08:07:19,440 INFO L376 atingTraceCheckCraig]: Compute interpolants for subsequence at non-pending call position 16 [2023-11-19 08:07:19,442 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2023-11-19 08:07:19,445 INFO L376 atingTraceCheckCraig]: Compute interpolants for subsequence at non-pending call position 21 [2023-11-19 08:07:19,446 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2023-11-19 08:07:19,449 INFO L376 atingTraceCheckCraig]: Compute interpolants for subsequence at non-pending call position 27 [2023-11-19 08:07:19,451 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2023-11-19 08:07:19,454 INFO L376 atingTraceCheckCraig]: Compute interpolants for subsequence at non-pending call position 32 [2023-11-19 08:07:19,456 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2023-11-19 08:07:19,459 INFO L376 atingTraceCheckCraig]: Compute interpolants for subsequence at non-pending call position 38 [2023-11-19 08:07:19,460 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2023-11-19 08:07:19,462 INFO L376 atingTraceCheckCraig]: Compute interpolants for subsequence at non-pending call position 43 [2023-11-19 08:07:19,464 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2023-11-19 08:07:19,467 INFO L376 atingTraceCheckCraig]: Compute interpolants for subsequence at non-pending call position 49 [2023-11-19 08:07:19,469 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2023-11-19 08:07:19,471 INFO L376 atingTraceCheckCraig]: Compute interpolants for subsequence at non-pending call position 54 [2023-11-19 08:07:19,473 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2023-11-19 08:07:19,476 INFO L134 CoverageAnalysis]: Checked inductivity of 180 backedges. 0 proven. 0 refuted. 0 times theorem prover too weak. 180 trivial. 0 not checked. [2023-11-19 08:07:19,477 INFO L136 FreeRefinementEngine]: Strategy CAMEL found an infeasible trace [2023-11-19 08:07:19,477 INFO L334 FreeRefinementEngine]: Using interpolant generator IpTcStrategyModuleSmtInterpolCraig [1766218871] [2023-11-19 08:07:19,477 INFO L158 FreeRefinementEngine]: IpTcStrategyModuleSmtInterpolCraig [1766218871] provided 1 perfect and 0 imperfect interpolant sequences [2023-11-19 08:07:19,478 INFO L185 FreeRefinementEngine]: Found 1 perfect and 0 imperfect interpolant sequences. [2023-11-19 08:07:19,478 INFO L198 FreeRefinementEngine]: Number of different interpolants: perfect sequences [4] imperfect sequences [] total 4 [2023-11-19 08:07:19,478 INFO L121 tionRefinementEngine]: Using interpolant automaton builder IpAbStrategyModuleStraightlineAll [120591216] [2023-11-19 08:07:19,478 INFO L85 oduleStraightlineAll]: Using 1 perfect interpolants to construct interpolant automaton [2023-11-19 08:07:19,479 INFO L571 AbstractCegarLoop]: INTERPOLANT automaton has 4 states [2023-11-19 08:07:19,479 INFO L100 FreeRefinementEngine]: Using predicate unifier PredicateUnifier provided by strategy CAMEL [2023-11-19 08:07:19,480 INFO L143 InterpolantAutomaton]: Constructing interpolant automaton starting with 4 interpolants. [2023-11-19 08:07:19,480 INFO L145 InterpolantAutomaton]: CoverageRelationStatistics Valid=5, Invalid=7, Unknown=0, NotChecked=0, Total=12 [2023-11-19 08:07:19,480 INFO L87 Difference]: Start difference. First operand 46 states and 62 transitions. Second operand has 4 states, 4 states have (on average 6.0) internal successors, (24), 4 states have internal predecessors, (24), 1 states have call successors, (10), 1 states have call predecessors, (10), 1 states have return successors, (10), 1 states have call predecessors, (10), 1 states have call successors, (10) [2023-11-19 08:07:19,565 INFO L144 Difference]: Subtrahend was deterministic. Have not used determinization. [2023-11-19 08:07:19,565 INFO L93 Difference]: Finished difference Result 131 states and 177 transitions. [2023-11-19 08:07:19,565 INFO L141 InterpolantAutomaton]: Switched to read-only mode: deterministic interpolant automaton has 4 states. [2023-11-19 08:07:19,566 INFO L78 Accepts]: Start accepts. Automaton has has 4 states, 4 states have (on average 6.0) internal successors, (24), 4 states have internal predecessors, (24), 1 states have call successors, (10), 1 states have call predecessors, (10), 1 states have return successors, (10), 1 states have call predecessors, (10), 1 states have call successors, (10) Word has length 71 [2023-11-19 08:07:19,566 INFO L84 Accepts]: Finished accepts. some prefix is accepted. [2023-11-19 08:07:19,568 INFO L225 Difference]: With dead ends: 131 [2023-11-19 08:07:19,568 INFO L226 Difference]: Without dead ends: 88 [2023-11-19 08:07:19,569 INFO L412 NwaCegarLoop]: 0 DeclaredPredicates, 25 GetRequests, 22 SyntacticMatches, 0 SemanticMatches, 3 ConstructedPredicates, 0 IntricatePredicates, 0 DeprecatedPredicates, 0 ImplicationChecksByTransitivity, 0.0s TimeCoverageRelationStatistics Valid=9, Invalid=11, Unknown=0, NotChecked=0, Total=20 [2023-11-19 08:07:19,570 INFO L413 NwaCegarLoop]: 47 mSDtfsCounter, 51 mSDsluCounter, 86 mSDsCounter, 0 mSdLazyCounter, 17 mSolverCounterSat, 31 mSolverCounterUnsat, 0 mSolverCounterUnknown, 0 mSolverCounterNotChecked, 0.1s Time, 0 mProtectedPredicate, 0 mProtectedAction, 51 SdHoareTripleChecker+Valid, 133 SdHoareTripleChecker+Invalid, 48 SdHoareTripleChecker+Unknown, 0 SdHoareTripleChecker+Unchecked, 0.0s SdHoareTripleChecker+Time, 31 IncrementalHoareTripleChecker+Valid, 17 IncrementalHoareTripleChecker+Invalid, 0 IncrementalHoareTripleChecker+Unknown, 0 IncrementalHoareTripleChecker+Unchecked, 0.1s IncrementalHoareTripleChecker+Time [2023-11-19 08:07:19,571 INFO L414 NwaCegarLoop]: SdHoareTripleChecker [51 Valid, 133 Invalid, 48 Unknown, 0 Unchecked, 0.0s Time], IncrementalHoareTripleChecker [31 Valid, 17 Invalid, 0 Unknown, 0 Unchecked, 0.1s Time] [2023-11-19 08:07:19,572 INFO L82 GeneralOperation]: Start minimizeSevpa. Operand 88 states. [2023-11-19 08:07:19,583 INFO L88 GeneralOperation]: Finished minimizeSevpa. Reduced states from 88 to 77. [2023-11-19 08:07:19,583 INFO L82 GeneralOperation]: Start removeUnreachable. Operand has 77 states, 54 states have (on average 1.1851851851851851) internal successors, (64), 54 states have internal predecessors, (64), 20 states have call successors, (20), 2 states have call predecessors, (20), 2 states have return successors, (20), 20 states have call predecessors, (20), 20 states have call successors, (20) [2023-11-19 08:07:19,585 INFO L88 GeneralOperation]: Finished removeUnreachable. Reduced from 77 states to 77 states and 104 transitions. [2023-11-19 08:07:19,585 INFO L78 Accepts]: Start accepts. Automaton has 77 states and 104 transitions. Word has length 71 [2023-11-19 08:07:19,586 INFO L84 Accepts]: Finished accepts. word is rejected. [2023-11-19 08:07:19,586 INFO L495 AbstractCegarLoop]: Abstraction has 77 states and 104 transitions. [2023-11-19 08:07:19,587 INFO L496 AbstractCegarLoop]: INTERPOLANT automaton has has 4 states, 4 states have (on average 6.0) internal successors, (24), 4 states have internal predecessors, (24), 1 states have call successors, (10), 1 states have call predecessors, (10), 1 states have return successors, (10), 1 states have call predecessors, (10), 1 states have call successors, (10) [2023-11-19 08:07:19,587 INFO L276 IsEmpty]: Start isEmpty. Operand 77 states and 104 transitions. [2023-11-19 08:07:19,589 INFO L282 IsEmpty]: Finished isEmpty. Found accepting run of length 72 [2023-11-19 08:07:19,589 INFO L187 NwaCegarLoop]: Found error trace [2023-11-19 08:07:19,589 INFO L195 NwaCegarLoop]: trace histogram [10, 10, 10, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1] [2023-11-19 08:07:19,589 WARN L477 AbstractCegarLoop]: Destroyed unattended storables created during the last iteration: SelfDestructingSolverStorable2 [2023-11-19 08:07:19,590 INFO L420 AbstractCegarLoop]: === Iteration 4 === Targeting ULTIMATE.startErr0ASSERT_VIOLATIONERROR_FUNCTION === [ULTIMATE.startErr0ASSERT_VIOLATIONERROR_FUNCTION] === [2023-11-19 08:07:19,590 INFO L160 PredicateUnifier]: Initialized classic predicate unifier [2023-11-19 08:07:19,590 INFO L85 PathProgramCache]: Analyzing trace with hash 1691811147, now seen corresponding path program 1 times [2023-11-19 08:07:19,591 INFO L118 FreeRefinementEngine]: Executing refinement strategy CAMEL [2023-11-19 08:07:19,591 INFO L334 FreeRefinementEngine]: Using trace check IpTcStrategyModuleSmtInterpolCraig [976926942] [2023-11-19 08:07:19,591 INFO L95 rtionOrderModulation]: Keeping assertion order NOT_INCREMENTALLY [2023-11-19 08:07:19,592 INFO L127 SolverBuilder]: Constructing new instance of SMTInterpol with explicit timeout -1 ms and remaining time -1 ms [2023-11-19 08:07:19,611 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2023-11-19 08:07:19,720 INFO L376 atingTraceCheckCraig]: Compute interpolants for subsequence at non-pending call position 5 [2023-11-19 08:07:19,722 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2023-11-19 08:07:19,724 INFO L376 atingTraceCheckCraig]: Compute interpolants for subsequence at non-pending call position 10 [2023-11-19 08:07:19,725 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2023-11-19 08:07:19,727 INFO L376 atingTraceCheckCraig]: Compute interpolants for subsequence at non-pending call position 16 [2023-11-19 08:07:19,728 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2023-11-19 08:07:19,729 INFO L376 atingTraceCheckCraig]: Compute interpolants for subsequence at non-pending call position 21 [2023-11-19 08:07:19,730 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2023-11-19 08:07:19,733 INFO L376 atingTraceCheckCraig]: Compute interpolants for subsequence at non-pending call position 27 [2023-11-19 08:07:19,734 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2023-11-19 08:07:19,736 INFO L376 atingTraceCheckCraig]: Compute interpolants for subsequence at non-pending call position 32 [2023-11-19 08:07:19,738 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2023-11-19 08:07:19,740 INFO L376 atingTraceCheckCraig]: Compute interpolants for subsequence at non-pending call position 38 [2023-11-19 08:07:19,741 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2023-11-19 08:07:19,743 INFO L376 atingTraceCheckCraig]: Compute interpolants for subsequence at non-pending call position 43 [2023-11-19 08:07:19,744 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2023-11-19 08:07:19,749 INFO L376 atingTraceCheckCraig]: Compute interpolants for subsequence at non-pending call position 49 [2023-11-19 08:07:19,751 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2023-11-19 08:07:19,753 INFO L376 atingTraceCheckCraig]: Compute interpolants for subsequence at non-pending call position 54 [2023-11-19 08:07:19,754 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat [2023-11-19 08:07:19,756 INFO L134 CoverageAnalysis]: Checked inductivity of 180 backedges. 0 proven. 0 refuted. 0 times theorem prover too weak. 180 trivial. 0 not checked. [2023-11-19 08:07:19,757 INFO L136 FreeRefinementEngine]: Strategy CAMEL found an infeasible trace [2023-11-19 08:07:19,757 INFO L334 FreeRefinementEngine]: Using interpolant generator IpTcStrategyModuleSmtInterpolCraig [976926942] [2023-11-19 08:07:19,757 INFO L158 FreeRefinementEngine]: IpTcStrategyModuleSmtInterpolCraig [976926942] provided 1 perfect and 0 imperfect interpolant sequences [2023-11-19 08:07:19,757 INFO L185 FreeRefinementEngine]: Found 1 perfect and 0 imperfect interpolant sequences. [2023-11-19 08:07:19,758 INFO L198 FreeRefinementEngine]: Number of different interpolants: perfect sequences [3] imperfect sequences [] total 3 [2023-11-19 08:07:19,758 INFO L121 tionRefinementEngine]: Using interpolant automaton builder IpAbStrategyModuleStraightlineAll [1450311498] [2023-11-19 08:07:19,758 INFO L85 oduleStraightlineAll]: Using 1 perfect interpolants to construct interpolant automaton [2023-11-19 08:07:19,761 INFO L571 AbstractCegarLoop]: INTERPOLANT automaton has 3 states [2023-11-19 08:07:19,761 INFO L100 FreeRefinementEngine]: Using predicate unifier PredicateUnifier provided by strategy CAMEL [2023-11-19 08:07:19,762 INFO L143 InterpolantAutomaton]: Constructing interpolant automaton starting with 3 interpolants. [2023-11-19 08:07:19,762 INFO L145 InterpolantAutomaton]: CoverageRelationStatistics Valid=3, Invalid=3, Unknown=0, NotChecked=0, Total=6 [2023-11-19 08:07:19,763 INFO L87 Difference]: Start difference. First operand 77 states and 104 transitions. Second operand has 3 states, 3 states have (on average 8.0) internal successors, (24), 3 states have internal predecessors, (24), 1 states have call successors, (10), 1 states have call predecessors, (10), 1 states have return successors, (10), 1 states have call predecessors, (10), 1 states have call successors, (10) [2023-11-19 08:07:19,807 INFO L144 Difference]: Subtrahend was deterministic. Have not used determinization. [2023-11-19 08:07:19,808 INFO L93 Difference]: Finished difference Result 161 states and 219 transitions. [2023-11-19 08:07:19,808 INFO L141 InterpolantAutomaton]: Switched to read-only mode: deterministic interpolant automaton has 3 states. [2023-11-19 08:07:19,808 INFO L78 Accepts]: Start accepts. Automaton has has 3 states, 3 states have (on average 8.0) internal successors, (24), 3 states have internal predecessors, (24), 1 states have call successors, (10), 1 states have call predecessors, (10), 1 states have return successors, (10), 1 states have call predecessors, (10), 1 states have call successors, (10) Word has length 71 [2023-11-19 08:07:19,809 INFO L84 Accepts]: Finished accepts. some prefix is accepted. [2023-11-19 08:07:19,811 INFO L225 Difference]: With dead ends: 161 [2023-11-19 08:07:19,811 INFO L226 Difference]: Without dead ends: 118 [2023-11-19 08:07:19,812 INFO L412 NwaCegarLoop]: 0 DeclaredPredicates, 24 GetRequests, 23 SyntacticMatches, 0 SemanticMatches, 1 ConstructedPredicates, 0 IntricatePredicates, 0 DeprecatedPredicates, 0 ImplicationChecksByTransitivity, 0.0s TimeCoverageRelationStatistics Valid=3, Invalid=3, Unknown=0, NotChecked=0, Total=6 [2023-11-19 08:07:19,813 INFO L413 NwaCegarLoop]: 90 mSDtfsCounter, 42 mSDsluCounter, 43 mSDsCounter, 0 mSdLazyCounter, 13 mSolverCounterSat, 1 mSolverCounterUnsat, 0 mSolverCounterUnknown, 0 mSolverCounterNotChecked, 0.0s Time, 0 mProtectedPredicate, 0 mProtectedAction, 42 SdHoareTripleChecker+Valid, 133 SdHoareTripleChecker+Invalid, 14 SdHoareTripleChecker+Unknown, 0 SdHoareTripleChecker+Unchecked, 0.0s SdHoareTripleChecker+Time, 1 IncrementalHoareTripleChecker+Valid, 13 IncrementalHoareTripleChecker+Invalid, 0 IncrementalHoareTripleChecker+Unknown, 0 IncrementalHoareTripleChecker+Unchecked, 0.0s IncrementalHoareTripleChecker+Time [2023-11-19 08:07:19,814 INFO L414 NwaCegarLoop]: SdHoareTripleChecker [42 Valid, 133 Invalid, 14 Unknown, 0 Unchecked, 0.0s Time], IncrementalHoareTripleChecker [1 Valid, 13 Invalid, 0 Unknown, 0 Unchecked, 0.0s Time] [2023-11-19 08:07:19,815 INFO L82 GeneralOperation]: Start minimizeSevpa. Operand 118 states. [2023-11-19 08:07:19,833 INFO L88 GeneralOperation]: Finished minimizeSevpa. Reduced states from 118 to 115. [2023-11-19 08:07:19,834 INFO L82 GeneralOperation]: Start removeUnreachable. Operand has 115 states, 81 states have (on average 1.1728395061728396) internal successors, (95), 81 states have internal predecessors, (95), 30 states have call successors, (30), 3 states have call predecessors, (30), 3 states have return successors, (30), 30 states have call predecessors, (30), 30 states have call successors, (30) [2023-11-19 08:07:19,836 INFO L88 GeneralOperation]: Finished removeUnreachable. Reduced from 115 states to 115 states and 155 transitions. [2023-11-19 08:07:19,836 INFO L78 Accepts]: Start accepts. Automaton has 115 states and 155 transitions. Word has length 71 [2023-11-19 08:07:19,837 INFO L84 Accepts]: Finished accepts. word is rejected. [2023-11-19 08:07:19,837 INFO L495 AbstractCegarLoop]: Abstraction has 115 states and 155 transitions. [2023-11-19 08:07:19,837 INFO L496 AbstractCegarLoop]: INTERPOLANT automaton has has 3 states, 3 states have (on average 8.0) internal successors, (24), 3 states have internal predecessors, (24), 1 states have call successors, (10), 1 states have call predecessors, (10), 1 states have return successors, (10), 1 states have call predecessors, (10), 1 states have call successors, (10) [2023-11-19 08:07:19,837 INFO L276 IsEmpty]: Start isEmpty. Operand 115 states and 155 transitions. [2023-11-19 08:07:19,839 INFO L282 IsEmpty]: Finished isEmpty. Found accepting run of length 72 [2023-11-19 08:07:19,839 INFO L187 NwaCegarLoop]: Found error trace [2023-11-19 08:07:19,839 INFO L195 NwaCegarLoop]: trace histogram [10, 10, 10, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1] [2023-11-19 08:07:19,839 WARN L477 AbstractCegarLoop]: Destroyed unattended storables created during the last iteration: SelfDestructingSolverStorable3 [2023-11-19 08:07:19,840 INFO L420 AbstractCegarLoop]: === Iteration 5 === Targeting ULTIMATE.startErr0ASSERT_VIOLATIONERROR_FUNCTION === [ULTIMATE.startErr0ASSERT_VIOLATIONERROR_FUNCTION] === [2023-11-19 08:07:19,840 INFO L160 PredicateUnifier]: Initialized classic predicate unifier [2023-11-19 08:07:19,840 INFO L85 PathProgramCache]: Analyzing trace with hash 1689964105, now seen corresponding path program 1 times [2023-11-19 08:07:19,840 INFO L118 FreeRefinementEngine]: Executing refinement strategy CAMEL [2023-11-19 08:07:19,841 INFO L334 FreeRefinementEngine]: Using trace check IpTcStrategyModuleSmtInterpolCraig [1159320128] [2023-11-19 08:07:19,841 INFO L95 rtionOrderModulation]: Keeping assertion order NOT_INCREMENTALLY [2023-11-19 08:07:19,841 INFO L127 SolverBuilder]: Constructing new instance of SMTInterpol with explicit timeout -1 ms and remaining time -1 ms [2023-11-19 08:07:19,859 INFO L136 AnnotateAndAsserter]: Conjunction of SSA is unsat