| Solver Name | Answer | CPU time | Wall clock time |
|---|---|---|---|
| FiberSCIP 2024-07-30 | UNSAT | 0.059681 | 0.060489 |
| Name | PB24/normalized-PB24/DEC-LIN/nordstrom/MIPLIB01/ dec/miplib2010/normalized-neos-777800.0.u.opb |
| MD5SUM | 85c335a5d84e5af9815833eb64512629 |
| Bench Category | DEC-LIN (decision problem, linear constraints, no UNSAT certificate) |
| Best result obtained on this benchmark | UNSAT |
| Best value of the objective obtained on this benchmark | |
| Best CPU time to get the best result obtained on this benchmark | 0.043724 |
| Has Objective Function | NO |
| Satisfiable | |
| (Un)Satisfiability was proved | |
| Best value of the objective function | |
| Optimality of the best value was proved | |
| Number of variables | 6400 |
| Total number of constraints | 476 |
| Number of constraints which are clauses | 4 |
| Number of constraints which are cardinality constraints (but not clauses) | 472 |
| Number of constraints which are nor clauses,nor cardinality constraints | 0 |
| Minimum length of a constraint | 2 |
| Maximum length of a constraint | 6400 |
| Number of terms in the objective function | 0 |
| Biggest coefficient in the objective function | 0 |
| Number of bits for the biggest coefficient in the objective function | 0 |
| Sum of the numbers in the objective function | 0 |
| Number of bits of the sum of numbers in the objective function | 0 |
| Biggest number in a constraint | 81 |
| Number of bits of the biggest number in a constraint | 7 |
| Biggest sum of numbers in a constraint | 6481 |
| Number of bits of the biggest sum of numbers | 13 |
| Number of products (including duplicates) | 0 |
| Sum of products size (including duplicates) | 0 |
| Number of different products | 0 |
| Sum of products size | 0 |
0.00/0.00 c The following solver is parallelized by UG version 1.0.0 [GitHash: e6e2b6ff-dirty] 0.00/0.00 c SCIP version 10.0.0 [precision: 8 byte] [memory: block] [mode: optimized] [LP solver: Soplex 7.1.1] [GitHash: 020d91813d] 0.00/0.00 c Copyright (c) 2002-2024 Zuse Institute Berlin (ZIB) 0.00/0.00 c External libraries: 0.00/0.00 c Soplex 7.1.1 Linear Programming Solver developed at Zuse Institute Berlin (soplex.zib.de) [GitHash: b4905e82] 0.00/0.00 c CppAD 20180000.0 Algorithmic Differentiation of C++ algorithms developed by B. Bell (github.com/coin-or/CppAD) 0.00/0.00 c AMPL/MP 690e9e7 AMPL .nl file reader library (github.com/ampl/mp) 0.00/0.00 c PaPILO 2.4.0 parallel presolve for integer and linear optimization (github.com/scipopt/papilo) 0.00/0.00 c Nauty 2.8.8 Computing Graph Automorphism Groups by Brendan D. McKay (users.cecs.anu.edu.au/~bdm/nauty) 0.00/0.00 c sassy 1.1 Symmetry preprocessor by Markus Anders (github.com/markusa4/sassy) 0.00/0.03 c Default LC presolving (default). 0.00/0.03 c ** Before presolving: virtualMemUsedAtLc = 42250240, getVmSize() = 42250240, SCIPgetMemUsed() = 17732372, SCIPgetMemTotal() = 20411100, SCIPgetMemExternEstim() = 6933666 0.00/0.03 c ** set memory limit for presolving in LC to 8.79608e+12 for SCIP ** 0.00/0.05 c === solved at Init === 0.00/0.05 c SCIP Status : c problem is solved [infeasible] 0.00/0.05 c Total Time : 0.06 0.00/0.05 c solving : 0.06 0.00/0.05 c presolving : 0.026296 (included in solving) 0.00/0.05 c B&B Tree : 0.00/0.05 c nodes (total) : 0 0.00/0.05 c Solution : 0.00/0.05 c Solutions found : 0 0.00/0.05 c Primal Bound : - 0.00/0.05 c Dual Bound : - 0.00/0.05 c Gap : - 0.00/0.05 s UNSATISFIABLE
ERROR: no interpretation found !
runsolver version 3.4.2 (svn: 4680) Copyright (C) 2010-2013 Olivier ROUSSEL
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
NUMA information:
number of nodes: 2
memory of node 0: 63931 MiB (58649 MiB free)
memory of node 1: 64510 MiB (50035 MiB free)
node distances:
10 21
21 10
command line: BIN/runsolver --timestamp --file-size-limit 102400 -w /tmp/evaluation-result-4464697-1722387371/watcher-4464697-1722387371 -o /tmp/evaluation-result-4464697-1722387371/solver-4464697-1722387371 -C 3600 -W 3700 -M 31000 --bin-var /tmp/runsolver-exch-nodeC027-1722378597-28892 --watchdog 3760 ./fscip settings/racing.prm HOME/instance-4464697-1722387371.opb -qsol -t 3600 -sth 1
running on 2 cores: 5,7
CPU governors:
performance: 5 7
Enforcing FSIZE limit: 104857600 KiB
Enforcing CPUTime limit (soft limit, will send SIGTERM then SIGKILL): 3600 seconds
Enforcing CPUTime limit (hard limit, will send SIGXCPU): 3630 seconds
Enforcing wall clock limit (soft limit, will send SIGTERM then SIGKILL): 3700 seconds
Enforcing VSIZE limit (soft limit, will send SIGTERM then SIGKILL): 31744000 KiB
Enforcing VSIZE limit (hard limit, stack expansion will fail with SIGSEGV, brk() and mmap() will return ENOMEM): 31795200 KiB
Linux 4.18.0-301.1.el8.x86_64
Starting watchdog thread
solver pid=34120, runsolver pid=34117
Current StackSize limit: 8192 KiB
[startup+0.060433 s]
# the end of solver process 34120 was just reported to runsolver
# Child status: 0
# cumulated CPU time of all completed processes: user=0.045776 s, system=0.013905 s
Solver just ended.
??? end of watcher thread
Dumping a history of the last processes samples
Child status: 0
Real time (s): 0.060489
CPU time (s): 0.059681
CPU user time (s): 0.045776
CPU system time (s): 0.013905
CPU usage (%): 98.6642
Max. virtual memory (cumulated for all children) (KiB): 0
Max. memory (cumulated for all children) (KiB): 0
getrusage(RUSAGE_CHILDREN,...) data:
user time used= 0.045776
system time used= 0.013905
maximum resident set size= 39492
integral shared memory size= 0
integral unshared data size= 0
integral unshared stack size= 0
page reclaims= 8251
page faults= 0
swaps= 0
block input operations= 0
block output operations= 0
messages sent= 0
messages received= 0
signals received= 0
voluntary context switches= 1
involuntary context switches= 2
# summary of solver processes directly reported to runsolver:
# pid: 34120
# total CPU time (s): 0.059681
# total CPU user time (s): 0.045776
# total CPU system time (s): 0.013905
??? join timestamper begins
??? join timestamper ends
??? end of timestamper thread
runsolver used 0.002264 second user time and 0.011299 second system time
The end
Begin job on nodeC027 at 2024-07-31 02:56:11 IDJOB=4464697 IDBENCH=164294 IDSOLVER=3092 FILE ID=nodeC027/4464697-1722387371 RUNJOBID= nodeC027-1722378597-28892 SLURM_JOB_ID= 8249850 Free space on /tmp= 889852 MiB SOLVER NAME= FiberSCIP 2024-07-30 BENCH NAME= PB24/normalized-PB24/DEC-LIN/nordstrom/MIPLIB01/dec/miplib2010/normalized-neos-777800.0.u.opb COMMAND LINE= ./fscip settings/racing.prm BENCHNAME -qsol -t TIMEOUT -sth 1 RUNSOLVER COMMAND LINE= BIN/runsolver --timestamp --file-size-limit 102400 -w /tmp/evaluation-result-4464697-1722387371/watcher-4464697-1722387371 -o /tmp/evaluation-result-4464697-1722387371/solver-4464697-1722387371 -C 3600 -W 3700 -M 31000 --bin-var /tmp/runsolver-exch-nodeC027-1722378597-28892 --watchdog 3760 ./fscip settings/racing.prm HOME/instance-4464697-1722387371.opb -qsol -t 3600 -sth 1 TIME LIMIT= 3600 seconds MEMORY LIMIT= 31000 MiB NBCORE= 2 MD5SUM BENCH= 85c335a5d84e5af9815833eb64512629 RANDOM SEED=2000602468 nodeC027.alineos.net Linux 4.18.0-301.1.el8.x86_64 #1 SMP Tue Apr 13 16:24:22 UTC 2021 /sys/devices/system/cpu/cpu0/cpufreq/scaling_governor: performance /proc/cpuinfo: processor : 0 vendor_id : GenuineIntel cpu family : 6 model : 79 model name : Intel(R) Xeon(R) CPU E5-2637 v4 @ 3.50GHz stepping : 1 microcode : 0xb00002a cpu MHz : 3661.138 cache size : 15360 KB physical id : 0 siblings : 4 core id : 0 cpu cores : 4 apicid : 0 initial apicid : 0 fpu : yes fpu_exception : yes cpuid level : 20 wp : yes flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe syscall nx pdpe1gb rdtscp lm constant_tsc arch_perfmon pebs bts rep_good nopl xtopology nonstop_tsc cpuid aperfmperf pni pclmulqdq dtes64 monitor ds_cpl vmx smx est tm2 ssse3 sdbg fma cx16 xtpr pdcm pcid dca sse4_1 sse4_2 x2apic movbe popcnt tsc_deadline_timer aes xsave avx f16c rdrand lahf_lm abm 3dnowprefetch cpuid_fault epb cat_l3 cdp_l3 invpcid_single pti ibrs ibpb stibp tpr_shadow vnmi flexpriority ept vpid ept_ad fsgsbase tsc_adjust bmi1 hle avx2 smep bmi2 erms invpcid rtm cqm rdt_a rdseed adx smap intel_pt xsaveopt cqm_llc cqm_occup_llc cqm_mbm_total cqm_mbm_local dtherm ida arat pln pts bugs : cpu_meltdown spectre_v1 spectre_v2 spec_store_bypass l1tf mds swapgs taa itlb_multihit bogomips : 6999.88 clflush size : 64 cache_alignment : 64 address sizes : 46 bits physical, 48 bits virtual power management: processor : 1 vendor_id : GenuineIntel cpu family : 6 model : 79 model name : Intel(R) Xeon(R) CPU E5-2637 v4 @ 3.50GHz stepping : 1 microcode : 0xb00002a cpu MHz : 3671.725 cache size : 15360 KB physical id : 1 siblings : 4 core id : 0 cpu cores : 4 apicid : 16 initial apicid : 16 fpu : yes fpu_exception : yes cpuid level : 20 wp : yes flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe syscall nx pdpe1gb rdtscp lm constant_tsc arch_perfmon pebs bts rep_good nopl xtopology nonstop_tsc cpuid aperfmperf pni pclmulqdq dtes64 monitor ds_cpl vmx smx est tm2 ssse3 sdbg fma cx16 xtpr pdcm pcid dca sse4_1 sse4_2 x2apic movbe popcnt tsc_deadline_timer aes xsave avx f16c rdrand lahf_lm abm 3dnowprefetch cpuid_fault epb cat_l3 cdp_l3 invpcid_single pti ibrs ibpb stibp tpr_shadow vnmi flexpriority ept vpid ept_ad fsgsbase tsc_adjust bmi1 hle avx2 smep bmi2 erms invpcid rtm cqm rdt_a rdseed adx smap intel_pt xsaveopt cqm_llc cqm_occup_llc cqm_mbm_total cqm_mbm_local dtherm ida arat pln pts bugs : cpu_meltdown spectre_v1 spectre_v2 spec_store_bypass l1tf mds swapgs taa itlb_multihit bogomips : 7006.31 clflush size : 64 cache_alignment : 64 address sizes : 46 bits physical, 48 bits virtual power management: processor : 2 vendor_id : GenuineIntel cpu family : 6 model : 79 model name : Intel(R) Xeon(R) CPU E5-2637 v4 @ 3.50GHz stepping : 1 microcode : 0xb00002a cpu MHz : 3600.304 cache size : 15360 KB physical id : 0 siblings : 4 core id : 1 cpu cores : 4 apicid : 2 initial apicid : 2 fpu : yes fpu_exception : yes cpuid level : 20 wp : yes flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe syscall nx pdpe1gb rdtscp lm constant_tsc arch_perfmon pebs bts rep_good nopl xtopology nonstop_tsc cpuid aperfmperf pni pclmulqdq dtes64 monitor ds_cpl vmx smx est tm2 ssse3 sdbg fma cx16 xtpr pdcm pcid dca sse4_1 sse4_2 x2apic movbe popcnt tsc_deadline_timer aes xsave avx f16c rdrand lahf_lm abm 3dnowprefetch cpuid_fault epb cat_l3 cdp_l3 invpcid_single pti ibrs ibpb stibp tpr_shadow vnmi flexpriority ept vpid ept_ad fsgsbase tsc_adjust bmi1 hle avx2 smep bmi2 erms invpcid rtm cqm rdt_a rdseed adx smap intel_pt xsaveopt cqm_llc cqm_occup_llc cqm_mbm_total cqm_mbm_local dtherm ida arat pln pts bugs : cpu_meltdown spectre_v1 spectre_v2 spec_store_bypass l1tf mds swapgs taa itlb_multihit bogomips : 6999.88 clflush size : 64 cache_alignment : 64 address sizes : 46 bits physical, 48 bits virtual power management: processor : 3 vendor_id : GenuineIntel cpu family : 6 model : 79 model name : Intel(R) Xeon(R) CPU E5-2637 v4 @ 3.50GHz stepping : 1 microcode : 0xb00002a cpu MHz : 3600.229 cache size : 15360 KB physical id : 1 siblings : 4 core id : 1 cpu cores : 4 apicid : 18 initial apicid : 18 fpu : yes fpu_exception : yes cpuid level : 20 wp : yes flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe syscall nx pdpe1gb rdtscp lm constant_tsc arch_perfmon pebs bts rep_good nopl xtopology nonstop_tsc cpuid aperfmperf pni pclmulqdq dtes64 monitor ds_cpl vmx smx est tm2 ssse3 sdbg fma cx16 xtpr pdcm pcid dca sse4_1 sse4_2 x2apic movbe popcnt tsc_deadline_timer aes xsave avx f16c rdrand lahf_lm abm 3dnowprefetch cpuid_fault epb cat_l3 cdp_l3 invpcid_single pti ibrs ibpb stibp tpr_shadow vnmi flexpriority ept vpid ept_ad fsgsbase tsc_adjust bmi1 hle avx2 smep bmi2 erms invpcid rtm cqm rdt_a rdseed adx smap intel_pt xsaveopt cqm_llc cqm_occup_llc cqm_mbm_total cqm_mbm_local dtherm ida arat pln pts bugs : cpu_meltdown spectre_v1 spectre_v2 spec_store_bypass l1tf mds swapgs taa itlb_multihit bogomips : 7006.31 clflush size : 64 cache_alignment : 64 address sizes : 46 bits physical, 48 bits virtual power management: processor : 4 vendor_id : GenuineIntel cpu family : 6 model : 79 model name : Intel(R) Xeon(R) CPU E5-2637 v4 @ 3.50GHz stepping : 1 microcode : 0xb00002a cpu MHz : 3661.187 cache size : 15360 KB physical id : 0 siblings : 4 core id : 2 cpu cores : 4 apicid : 4 initial apicid : 4 fpu : yes fpu_exception : yes cpuid level : 20 wp : yes flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe syscall nx pdpe1gb rdtscp lm constant_tsc arch_perfmon pebs bts rep_good nopl xtopology nonstop_tsc cpuid aperfmperf pni pclmulqdq dtes64 monitor ds_cpl vmx smx est tm2 ssse3 sdbg fma cx16 xtpr pdcm pcid dca sse4_1 sse4_2 x2apic movbe popcnt tsc_deadline_timer aes xsave avx f16c rdrand lahf_lm abm 3dnowprefetch cpuid_fault epb cat_l3 cdp_l3 invpcid_single pti ibrs ibpb stibp tpr_shadow vnmi flexpriority ept vpid ept_ad fsgsbase tsc_adjust bmi1 hle avx2 smep bmi2 erms invpcid rtm cqm rdt_a rdseed adx smap intel_pt xsaveopt cqm_llc cqm_occup_llc cqm_mbm_total cqm_mbm_local dtherm ida arat pln pts bugs : cpu_meltdown spectre_v1 spectre_v2 spec_store_bypass l1tf mds swapgs taa itlb_multihit bogomips : 6999.88 clflush size : 64 cache_alignment : 64 address sizes : 46 bits physical, 48 bits virtual power management: processor : 5 vendor_id : GenuineIntel cpu family : 6 model : 79 model name : Intel(R) Xeon(R) CPU E5-2637 v4 @ 3.50GHz stepping : 1 microcode : 0xb00002a cpu MHz : 3665.761 cache size : 15360 KB physical id : 1 siblings : 4 core id : 2 cpu cores : 4 apicid : 20 initial apicid : 20 fpu : yes fpu_exception : yes cpuid level : 20 wp : yes flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe syscall nx pdpe1gb rdtscp lm constant_tsc arch_perfmon pebs bts rep_good nopl xtopology nonstop_tsc cpuid aperfmperf pni pclmulqdq dtes64 monitor ds_cpl vmx smx est tm2 ssse3 sdbg fma cx16 xtpr pdcm pcid dca sse4_1 sse4_2 x2apic movbe popcnt tsc_deadline_timer aes xsave avx f16c rdrand lahf_lm abm 3dnowprefetch cpuid_fault epb cat_l3 cdp_l3 invpcid_single pti ibrs ibpb stibp tpr_shadow vnmi flexpriority ept vpid ept_ad fsgsbase tsc_adjust bmi1 hle avx2 smep bmi2 erms invpcid rtm cqm rdt_a rdseed adx smap intel_pt xsaveopt cqm_llc cqm_occup_llc cqm_mbm_total cqm_mbm_local dtherm ida arat pln pts bugs : cpu_meltdown spectre_v1 spectre_v2 spec_store_bypass l1tf mds swapgs taa itlb_multihit bogomips : 7006.31 clflush size : 64 cache_alignment : 64 address sizes : 46 bits physical, 48 bits virtual power management: processor : 6 vendor_id : GenuineIntel cpu family : 6 model : 79 model name : Intel(R) Xeon(R) CPU E5-2637 v4 @ 3.50GHz stepping : 1 microcode : 0xb00002a cpu MHz : 3599.972 cache size : 15360 KB physical id : 0 siblings : 4 core id : 3 cpu cores : 4 apicid : 6 initial apicid : 6 fpu : yes fpu_exception : yes cpuid level : 20 wp : yes flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe syscall nx pdpe1gb rdtscp lm constant_tsc arch_perfmon pebs bts rep_good nopl xtopology nonstop_tsc cpuid aperfmperf pni pclmulqdq dtes64 monitor ds_cpl vmx smx est tm2 ssse3 sdbg fma cx16 xtpr pdcm pcid dca sse4_1 sse4_2 x2apic movbe popcnt tsc_deadline_timer aes xsave avx f16c rdrand lahf_lm abm 3dnowprefetch cpuid_fault epb cat_l3 cdp_l3 invpcid_single pti ibrs ibpb stibp tpr_shadow vnmi flexpriority ept vpid ept_ad fsgsbase tsc_adjust bmi1 hle avx2 smep bmi2 erms invpcid rtm cqm rdt_a rdseed adx smap intel_pt xsaveopt cqm_llc cqm_occup_llc cqm_mbm_total cqm_mbm_local dtherm ida arat pln pts bugs : cpu_meltdown spectre_v1 spectre_v2 spec_store_bypass l1tf mds swapgs taa itlb_multihit bogomips : 6999.88 clflush size : 64 cache_alignment : 64 address sizes : 46 bits physical, 48 bits virtual power management: processor : 7 vendor_id : GenuineIntel cpu family : 6 model : 79 model name : Intel(R) Xeon(R) CPU E5-2637 v4 @ 3.50GHz stepping : 1 microcode : 0xb00002a cpu MHz : 3674.541 cache size : 15360 KB physical id : 1 siblings : 4 core id : 3 cpu cores : 4 apicid : 22 initial apicid : 22 fpu : yes fpu_exception : yes cpuid level : 20 wp : yes flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe syscall nx pdpe1gb rdtscp lm constant_tsc arch_perfmon pebs bts rep_good nopl xtopology nonstop_tsc cpuid aperfmperf pni pclmulqdq dtes64 monitor ds_cpl vmx smx est tm2 ssse3 sdbg fma cx16 xtpr pdcm pcid dca sse4_1 sse4_2 x2apic movbe popcnt tsc_deadline_timer aes xsave avx f16c rdrand lahf_lm abm 3dnowprefetch cpuid_fault epb cat_l3 cdp_l3 invpcid_single pti ibrs ibpb stibp tpr_shadow vnmi flexpriority ept vpid ept_ad fsgsbase tsc_adjust bmi1 hle avx2 smep bmi2 erms invpcid rtm cqm rdt_a rdseed adx smap intel_pt xsaveopt cqm_llc cqm_occup_llc cqm_mbm_total cqm_mbm_local dtherm ida arat pln pts bugs : cpu_meltdown spectre_v1 spectre_v2 spec_store_bypass l1tf mds swapgs taa itlb_multihit bogomips : 7006.31 clflush size : 64 cache_alignment : 64 address sizes : 46 bits physical, 48 bits virtual power management: /proc/meminfo: MemTotal: 131524600 kB MemFree: 111293624 kB MemAvailable: 111305576 kB Buffers: 102564 kB Cached: 743016 kB SwapCached: 0 kB Active: 430628 kB Inactive: 19285052 kB Active(anon): 1560 kB Inactive(anon): 18890208 kB Active(file): 429068 kB Inactive(file): 394844 kB Unevictable: 0 kB Mlocked: 0 kB SwapTotal: 131071996 kB SwapFree: 131071996 kB Dirty: 28364 kB Writeback: 0 kB AnonPages: 18867748 kB Mapped: 123824 kB Shmem: 21336 kB KReclaimable: 55376 kB Slab: 136448 kB SReclaimable: 55376 kB SUnreclaim: 81072 kB KernelStack: 4188 kB PageTables: 45928 kB NFS_Unstable: 0 kB Bounce: 0 kB WritebackTmp: 0 kB CommitLimit: 196834296 kB Committed_AS: 20214128 kB VmallocTotal: 34359738367 kB VmallocUsed: 0 kB VmallocChunk: 0 kB Percpu: 10080 kB HardwareCorrupted: 0 kB AnonHugePages: 5711872 kB ShmemHugePages: 0 kB ShmemPmdMapped: 0 kB FileHugePages: 0 kB FilePmdMapped: 0 kB HugePages_Total: 0 HugePages_Free: 0 HugePages_Rsvd: 0 HugePages_Surp: 0 Hugepagesize: 2048 kB Hugetlb: 0 kB DirectMap4k: 150228 kB DirectMap2M: 9060352 kB DirectMap1G: 126877696 kB Free space on /tmp at the end= 889824 MiB End job on nodeC027 at 2024-07-31 02:56:12