Trace number 2077599

Some explanations

A solver is run under the control of another program named runsolver. runsolver is in charge of imposing the CPU time limit and the memory limit to the solver. It also monitors some information about the process. The trace of the execution of a solver is divided into four (or five) parts:
  1. SOLVER DATA
    This is the output of the solver (stdout and stderr).
    Note that some very long lines in this section may be truncated by your web browser ! In such a case, you may want to use the "Download as text" link to get the trace as a text file.

    When the --timestamp option is passed to the runsolver program, each line output by the solver is prepended with a timestamp which indicates at what time the line was output by the solver. Times are relative to the start of the program, given in seconds. The first timestamp (if present) is estimated CPU time. The last timestamp is wall clock time.

    As some 'v lines' may be very long (sometimes several megabytes), the 'v line' output by your solver may be split on several lines to help limit the size of the trace recorded in the database. In any case, the exact output of your solver is preserved in a trace file.
  2. VERIFIER DATA
    The output of the solver is piped to a verifier program which will search a value line "v " and, if found, will check that the given interpretation satisfies all constraints.
  3. CONVERSION SCRIPT DATA (Optionnal)
    When a conversion script is used, this section shows the messages that were output by the conversion script.
  4. WATCHER DATA
    This is the informations gathered by the runsolver program. It first prints the different limits. There's a first limit on CPU time set to X seconds (see the parameters in the trace). After this time has ellapsed, runsolver sends a SIGTERM and 2 seconds later a SIGKILL to the solver. For safety, there's also another limit set to X+30 seconds which will send a SIGXPU to the solver. The last limit is on the virtual memory used by the process (see the parameters in the trace).
    Every ten seconds, the runsolver process fetches the content of /proc/loadavg, /proc/pid/stat and /proc/pid/statm (see man proc) and prints it as raw data. This is only recorded in case we need to investigate the behaviour of a solver. The memory used by the solver (vsize) is also given every ten seconds.
    When the solver exits, runsolver prints some informations such as status and time. CPU usage is the ratio CPU Time/Real Time.
  5. LAUNCHER DATA
    These informations are related to the script which will launch the solver. The most important informations are the command line given to the solver, the md5sum of the different files and the dump of the /proc/cpuinfo and /proc/meminfo which provides some useful information on the computer.

Solver answer on this benchmark

Solver NameAnswerCPU timeWall clock time
pcs 0.3.2SAT 12.0622 12.1837

DiagnosticValue
ASSIGNMENTS411

General information on the benchmark

Namecsp/wordsHerald/
normalized-crossword-m1-words-19-04.xml
MD5SUM8223b3be8400c707a14e61e5793f2bd8
Bench CategoryN-ARY-INT (n-ary constraints in intension)
Best result obtained on this benchmarkSAT
Best CPU time to get the best result obtained on this benchmark12.0622
Satisfiable
(Un)Satisfiability was proved
Number of variables296
Number of constraints2314
Maximum constraint arity26
Maximum domain size26
Number of constraints which are defined in extension132
Number of constraints which are defined in intension2182
Global constraints used (with number of constraints)

Solver Data 

0.00/0.02	c small-domain mode
0.00/0.05	c Seed is 421270410
0.00/0.05	c Constructing HOME/instance-2077599-1247715159.xml  with 28048 constraints
0.27/0.35	c Solving 411 backtracks 6 restarts
11.96/12.18	s SATISFIABLE
11.96/12.18	c V0=18, V1=14, V2=13, V3=0, V4=17, V5=11, V6=0, V7=8, V8=18, V9=18, V10=4, V11=25, V12=0, V13=1, V14=17, V15=0, V16=12, V17=22, V18=7, V19=14, V20=17, V21=4, V22=0, V23=1, V24=18, V25=14, V26=11, V27=21, V28=4, V29=12, V30=14, V31=14, V32=17, V33=4, V34=4, V35=0, V36=17, V37=4, V38=3, V39=18, V40=14, V41=11, V42=3, V43=8, V44=4, V45=17, V46=24, V47=0, V48=11, V49=19, V50=0, V51=0, V52=17, V53=12, V54=14, V55=5, V56=19, V57=4, V58=0, V59=19, V60=14, V61=8, V62=11, V63=11, V64=8, V65=19, V66=17, V67=4, V68=0, V69=15, V70=0, V71=11, V72=8, V73=19, V74=4, V75=3, V76=20, V77=18, V78=4, V79=18, V80=4, V81=13, V82=2, V83=24, V84=2, V85=11, V86=14, V87=15, V88=4, V89=3, V90=8, V91=0, V92=18, V93=12, V94=0, V95=6, V96=6, V97=14, V98=19, V99=24, V100=4, V101=0, V102=17, V103=13, V104=14, V105=3, V106=4, V107=18, V108=18, V109=0, V110=0, V111=6, V112=4, V113=13, V114=14, V115=17, V116=5, V117=17, V118=14, V119=0, V120=18, V121=18, V122=15, V123=20, V124=13, V125=11, V126=14, V127=13, V128=4, V129=17, V130=0, V131=15, V132=19, V133=22, V134=8, V135=17, V136=24, V137=22, V138=4, V139=13, V140=19, V141=0, V142=13, V143=4, V144=22, V145=8, V146=3, V147=0, V148=11, V149=8, V150=13, V151=4, V152=11, V153=1, V154=0, V155=12, V156=8, V157=17, V158=4, V159=25, V160=8, V161=13, V162=2, V163=0, V164=11, V165=4, V166=2, V167=1, V168=11, V169=20, V170=17, V171=20, V172=25, V173=8, V174=12, V175=0, V176=23, V177=0, V178=15, V179=19, V180=18, V181=17, V182=8, V183=4, V184=17, V185=4, V186=3, V187=4, V188=2, V189=13, V190=4, V191=19, V192=14, V193=17, V194=8, V195=14, V196=13, V197=0, V198=2, V199=14, V200=17, V201=13, V202=18, V203=20, V204=13, V205=8, V206=12, V207=15, V208=11, V209=4, V210=12, V211=4, V212=13, V213=19, V214=4, V215=3, V216=22, V217=0, V218=17, V219=13, V220=14, V221=0, V222=19, V223=22, V224=4, V225=8, V226=4, V227=3, V228=4, V229=13, V230=0, V231=19, V232=4, V233=0, V234=13, V235=24, V236=0, V237=11, V238=11, V239=0, V240=2, V241=4, V242=17, V243=0, V244=4, V245=11, V246=14, V247=5, V248=19, V249=18, V250=0, V251=13, V252=13, V253=14, V254=24, V255=4, V256=17, V257=0, V258=1, V259=0, V260=19, V261=4, V262=18, V263=13, V264=4, V265=0, V266=10, V267=13, V268=0, V269=19, V270=20, V271=17, V272=0, V273=11, V274=17, V275=0, V276=2, V277=4, V278=3, V279=7, V280=4, V281=17, V282=1, V283=18, V284=18, V285=15, V286=8, V287=3, V288=4, V289=17, V290=24, V291=15, V292=7, V293=14, V294=13, V295=24, 
11.96/12.18	v 18 14 13 0 17 11 0 8 18 18 4 25 0 1 17 0 12 22 7 14 17 4 0 1 18 14 11 21 4 12 14 14 17 4 4 0 17 4 3 18 14 11 3 8 4 17 24 0 11 19 0 0 17 12 14 5 19 4 0 19 14 8 11 11 8 19 17 4 0 15 0 11 8 19 4 3 20 18 4 18 4 13 2 24 2 11 14 15 4 3 8 0 18 12 0 6 6 14 19 24 4 0 17 13 14 3 4 18 18 0 0 6 4 13 14 17 5 17 14 0 18 18 15 20 13 11 14 13 4 17 0 15 19 22 8 17 24 22 4 13 19 0 13 4 22 8 3 0 11 8 13 4 11 1 0 12 8 17 4 25 8 13 2 0 11 4 2 1 11 20 17 20 25 8 12 0 23 0 15 19 18 17 8 4 17 4 3 4 2 13 4 19 14 17 8 14 13 0 2 14 17 13 18 20 13 8 12 15 11 4 12 4 13 19 4 3 22 0 17 13 14 0 19 22 4 8 4 3 4 13 0 19 4 0 13 24 0 11 11 0 2 4 17 0 4 11 14 5 19 18 0 13 13 14 24 4 17 0 1 0 19 4 18 13 4 0 10 13 0 19 20 17 0 11 17 0 2 4 3 7 4 17 1 18 18 15 8 3 4 17 24 15 7 14 13 24 
11.96/12.18	d ASSIGNMENTS 411

Verifier Data 

OK

Watcher Data 

runsolver version 3.2.9 (svn:492) (c) roussel@cril.univ-artois.fr

command line: BIN/runsolver --timestamp -w /tmp/evaluation-result-2077599-1247715159/watcher-2077599-1247715159 -o /tmp/evaluation-result-2077599-1247715159/solver-2077599-1247715159 -C 1800 -W 2000 -M 900 HOME/pcssolve -s 421270410 HOME/instance-2077599-1247715159.xml 

Enforcing CPUTime limit (soft limit, will send SIGTERM then SIGKILL): 1800 seconds
Enforcing CPUTime limit (hard limit, will send SIGXCPU): 1830 seconds
Enforcing wall clock limit (soft limit, will send SIGTERM then SIGKILL): 2000 seconds
Enforcing VSIZE limit (soft limit, will send SIGTERM then SIGKILL): 921600 KiB
Enforcing VSIZE limit (hard limit, stack expansion will fail with SIGSEGV, brk() and mmap() will return ENOMEM): 972800 KiB
Current StackSize limit: 10240 KiB


[startup+0 s]
/proc/loadavg: 3.12 2.61 2.26 4/83 9772
/proc/meminfo: memFree=1528856/2055920 swapFree=4192812/4192956
[pid=9772] ppid=9770 vsize=5356 CPUtime=0
/proc/9772/stat : 9772 (pcssolve) R 9770 9772 9309 0 -1 4194304 290 0 0 0 0 0 0 0 21 0 1 0 58580703 5484544 241 996147200 4194304 4889804 548682068800 18446744073709551615 234211568287 0 65538 4100 65536 0 0 0 17 1 0 0
/proc/9772/statm: 1339 241 200 169 0 50 0
[pid=9773] ppid=9772 vsize=100 CPUtime=0
/proc/9773/stat : 9773 (fgrep) R 9772 9772 9309 0 -1 4194304 24 0 0 0 0 0 0 0 22 0 1 0 58580704 102400 3 996147200 0 0 548682069725 18446744073709551615 234211568935 0 0 4096 0 0 0 0 17 1 0 0
/proc/9773/statm: 25 3 0 0 0 2 0
[pid=9774] ppid=9772 vsize=5356 CPUtime=0
/proc/9774/stat : 9774 (pcssolve) R 9772 9772 9309 0 -1 4194368 0 0 0 0 0 0 0 0 21 0 1 0 58580704 5484544 241 996147200 4194304 4889804 548682068800 18446744073709551615 234211568287 0 65538 4100 65536 0 0 0 17 1 0 0
/proc/9774/statm: 1339 241 200 169 0 50 0

[startup+0.103737 s]
/proc/loadavg: 3.12 2.61 2.26 4/83 9772
/proc/meminfo: memFree=1528856/2055920 swapFree=4192812/4192956
[pid=9772] ppid=9770 vsize=5368 CPUtime=0.07
/proc/9772/stat : 9772 (pcs.small) R 9770 9772 9309 0 -1 4194304 995 974 0 0 7 0 0 0 18 0 1 0 58580703 5496832 604 996147200 134512640 135095119 4294956304 18446744073709551615 134741532 0 0 4096 0 0 0 0 17 1 0 0
/proc/9772/statm: 1342 604 375 142 0 296 0
Current children cumulated CPU time (s) 0.07
Current children cumulated vsize (KiB) 5368

[startup+0.202754 s]
/proc/loadavg: 3.12 2.61 2.26 4/83 9772
/proc/meminfo: memFree=1528856/2055920 swapFree=4192812/4192956
[pid=9772] ppid=9770 vsize=7732 CPUtime=0.17
/proc/9772/stat : 9772 (pcs.small) R 9770 9772 9309 0 -1 4194304 1493 974 0 0 17 0 0 0 18 0 1 0 58580703 7917568 1069 996147200 134512640 135095119 4294956304 18446744073709551615 2252571 0 0 4096 0 0 0 0 17 1 0 0
/proc/9772/statm: 1933 1069 388 142 0 887 0
Current children cumulated CPU time (s) 0.17
Current children cumulated vsize (KiB) 7732

[startup+0.302767 s]
/proc/loadavg: 3.12 2.61 2.26 4/83 9772
/proc/meminfo: memFree=1528856/2055920 swapFree=4192812/4192956
[pid=9772] ppid=9770 vsize=9520 CPUtime=0.27
/proc/9772/stat : 9772 (pcs.small) R 9770 9772 9309 0 -1 4194304 2147 974 0 0 27 0 0 0 19 0 1 0 58580703 9748480 1529 996147200 134512640 135095119 4294956304 18446744073709551615 4158919152 0 0 4096 0 0 0 0 17 1 0 0
/proc/9772/statm: 2380 1529 388 142 0 1334 0
Current children cumulated CPU time (s) 0.27
Current children cumulated vsize (KiB) 9520

[startup+0.701813 s]
/proc/loadavg: 3.12 2.61 2.26 4/83 9772
/proc/meminfo: memFree=1528856/2055920 swapFree=4192812/4192956
[pid=9772] ppid=9770 vsize=11788 CPUtime=0.67
/proc/9772/stat : 9772 (pcs.small) R 9770 9772 9309 0 -1 4194304 2905 974 0 0 66 1 0 0 23 0 1 0 58580703 12070912 2184 996147200 134512640 135095119 4294956304 18446744073709551615 134918190 0 0 4096 0 0 0 0 17 1 0 0
/proc/9772/statm: 2947 2184 400 142 0 1901 0
Current children cumulated CPU time (s) 0.67
Current children cumulated vsize (KiB) 11788

[startup+1.50192 s]
/proc/loadavg: 3.12 2.61 2.26 3/84 9778
/proc/meminfo: memFree=1521488/2055920 swapFree=4192812/4192956
[pid=9772] ppid=9770 vsize=11812 CPUtime=1.46
/proc/9772/stat : 9772 (pcs.small) R 9770 9772 9309 0 -1 4194304 2927 974 0 0 145 1 0 0 25 0 1 0 58580703 12095488 2185 996147200 134512640 135095119 4294956304 18446744073709551615 134927013 0 0 4096 0 0 0 0 17 1 0 0
/proc/9772/statm: 2953 2185 400 142 0 1907 0
Current children cumulated CPU time (s) 1.46
Current children cumulated vsize (KiB) 11812

[startup+3.10112 s]
/proc/loadavg: 3.12 2.61 2.26 3/84 9778
/proc/meminfo: memFree=1521424/2055920 swapFree=4192812/4192956
[pid=9772] ppid=9770 vsize=11896 CPUtime=3.05
/proc/9772/stat : 9772 (pcs.small) R 9770 9772 9309 0 -1 4194304 2944 974 0 0 304 1 0 0 25 0 1 0 58580703 12181504 2202 996147200 134512640 135095119 4294956304 18446744073709551615 134918203 0 0 4096 0 0 0 0 17 1 0 0
/proc/9772/statm: 2974 2202 400 142 0 1928 0
Current children cumulated CPU time (s) 3.05
Current children cumulated vsize (KiB) 11896

[startup+6.30152 s]
/proc/loadavg: 3.03 2.60 2.26 3/84 9778
/proc/meminfo: memFree=1521104/2055920 swapFree=4192812/4192956
[pid=9772] ppid=9770 vsize=12008 CPUtime=6.22
/proc/9772/stat : 9772 (pcs.small) R 9770 9772 9309 0 -1 4194304 3013 974 0 0 621 1 0 0 25 0 1 0 58580703 12296192 2230 996147200 134512640 135095119 4294956304 18446744073709551615 134918163 0 0 4096 0 0 0 0 17 1 0 0
/proc/9772/statm: 3002 2230 400 142 0 1956 0
Current children cumulated CPU time (s) 6.22
Current children cumulated vsize (KiB) 12008

Solver just ended. Dumping a history of the last processes samples

[startup+6.40154 s]
/proc/loadavg: 3.03 2.60 2.26 3/84 9778
/proc/meminfo: memFree=1521104/2055920 swapFree=4192812/4192956
[pid=9772] ppid=9770 vsize=12008 CPUtime=6.32
/proc/9772/stat : 9772 (pcs.small) R 9770 9772 9309 0 -1 4194304 3013 974 0 0 631 1 0 0 25 0 1 0 58580703 12296192 2230 996147200 134512640 135095119 4294956304 18446744073709551615 134927036 0 0 4096 0 0 0 0 17 1 0 0
/proc/9772/statm: 3002 2230 400 142 0 1956 0
Current children cumulated CPU time (s) 6.32
Current children cumulated vsize (KiB) 12008

[startup+9.60194 s]
/proc/loadavg: 2.95 2.59 2.26 3/84 9778
/proc/meminfo: memFree=1521104/2055920 swapFree=4192812/4192956
[pid=9772] ppid=9770 vsize=12008 CPUtime=9.49
/proc/9772/stat : 9772 (pcs.small) R 9770 9772 9309 0 -1 4194304 3014 974 0 0 948 1 0 0 25 0 1 0 58580703 12296192 2231 996147200 134512640 135095119 4294956304 18446744073709551615 134918211 0 0 4096 0 0 0 0 17 1 0 0
/proc/9772/statm: 3002 2231 400 142 0 1956 0
Current children cumulated CPU time (s) 9.49
Current children cumulated vsize (KiB) 12008

[startup+11.2011 s]
/proc/loadavg: 2.95 2.59 2.26 3/84 9778
/proc/meminfo: memFree=1521104/2055920 swapFree=4192812/4192956
[pid=9772] ppid=9770 vsize=12064 CPUtime=11.07
/proc/9772/stat : 9772 (pcs.small) R 9770 9772 9309 0 -1 4194304 3017 974 0 0 1106 1 0 0 25 0 1 0 58580703 12353536 2234 996147200 134512640 135095119 4294956304 18446744073709551615 134927029 0 0 4096 0 0 0 0 17 1 0 0
/proc/9772/statm: 3016 2234 400 142 0 1970 0
Current children cumulated CPU time (s) 11.07
Current children cumulated vsize (KiB) 12064

[startup+11.6012 s]
/proc/loadavg: 2.95 2.59 2.26 3/84 9778
/proc/meminfo: memFree=1521104/2055920 swapFree=4192812/4192956
[pid=9772] ppid=9770 vsize=12064 CPUtime=11.47
/proc/9772/stat : 9772 (pcs.small) R 9770 9772 9309 0 -1 4194304 3019 974 0 0 1146 1 0 0 25 0 1 0 58580703 12353536 2236 996147200 134512640 135095119 4294956304 18446744073709551615 134927080 0 0 4096 0 0 0 0 17 1 0 0
/proc/9772/statm: 3016 2236 400 142 0 1970 0
Current children cumulated CPU time (s) 11.47
Current children cumulated vsize (KiB) 12064

[startup+12.0012 s]
/proc/loadavg: 2.95 2.59 2.26 3/84 9778
/proc/meminfo: memFree=1521104/2055920 swapFree=4192812/4192956
[pid=9772] ppid=9770 vsize=12384 CPUtime=11.86
/proc/9772/stat : 9772 (pcs.small) R 9770 9772 9309 0 -1 4194304 3127 974 0 0 1185 1 0 0 25 0 1 0 58580703 12681216 2263 996147200 134512640 135095119 4294956304 18446744073709551615 134927023 0 0 4096 0 0 0 0 17 1 0 0
/proc/9772/statm: 3096 2263 400 142 0 2050 0
Current children cumulated CPU time (s) 11.86
Current children cumulated vsize (KiB) 12384

[startup+12.1013 s]
/proc/loadavg: 2.95 2.59 2.26 3/84 9778
/proc/meminfo: memFree=1520848/2055920 swapFree=4192812/4192956
[pid=9772] ppid=9770 vsize=12384 CPUtime=11.96
/proc/9772/stat : 9772 (pcs.small) R 9770 9772 9309 0 -1 4194304 3127 974 0 0 1195 1 0 0 25 0 1 0 58580703 12681216 2263 996147200 134512640 135095119 4294956304 18446744073709551615 134617017 0 0 4096 0 0 0 0 17 1 0 0
/proc/9772/statm: 3096 2263 400 142 0 2050 0
Current children cumulated CPU time (s) 11.96
Current children cumulated vsize (KiB) 12384

Child status: 0
Real time (s): 12.1837
CPU time (s): 12.0622
CPU user time (s): 12.0412
CPU system time (s): 0.020996
CPU usage (%): 99.0022
Max. virtual memory (cumulated for all children) (KiB): 12384

getrusage(RUSAGE_CHILDREN,...) data:
user time used= 12.0412
system time used= 0.020996
maximum resident set size= 0
integral shared memory size= 0
integral unshared data size= 0
integral unshared stack size= 0
page reclaims= 4123
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= 21
involuntary context switches= 522

runsolver used 0.011998 second user time and 0.053991 second system time

The end

Launcher Data 

Begin job on node54 at 2009-07-16 05:32:39
IDJOB=2077599
IDBENCH=56630
IDSOLVER=733
FILE ID=node54/2077599-1247715159
PBS_JOBID= 9521379
Free space on /tmp= 66292 MiB

SOLVER NAME= pcs 0.2
BENCH NAME= CPAI08/csp/wordsHerald/normalized-crossword-m1-words-19-04.xml
COMMAND LINE= HOME/pcssolve -s RANDOMSEED BENCHNAME
RUNSOLVER COMMAND LINE= BIN/runsolver --timestamp -w /tmp/evaluation-result-2077599-1247715159/watcher-2077599-1247715159 -o /tmp/evaluation-result-2077599-1247715159/solver-2077599-1247715159 -C 1800 -W 2000 -M 900  HOME/pcssolve -s 421270410 HOME/instance-2077599-1247715159.xml

TIME LIMIT= 1800 seconds
MEMORY LIMIT= 900 MiB
MAX NB THREAD= 0

MD5SUM BENCH= 8223b3be8400c707a14e61e5793f2bd8
RANDOM SEED=421270410

node54.alineos.net Linux 2.6.9-22.EL.rootsmp #1 SMP Mon Oct 3 08:59:52 CEST 2005

/proc/cpuinfo:
processor	: 0
vendor_id	: GenuineIntel
cpu family	: 15
model		: 4
model name	:                   Intel(R) Xeon(TM) CPU 3.00GHz
stepping	: 3
cpu MHz		: 3000.232
cache size	: 2048 KB
fpu		: yes
fpu_exception	: yes
cpuid level	: 5
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 syscall nx lm pni monitor ds_cpl cid cx16 xtpr
bogomips	: 5914.62
clflush size	: 64
cache_alignment	: 128
address sizes	: 36 bits physical, 48 bits virtual
power management:

processor	: 1
vendor_id	: GenuineIntel
cpu family	: 15
model		: 4
model name	:                   Intel(R) Xeon(TM) CPU 3.00GHz
stepping	: 3
cpu MHz		: 3000.232
cache size	: 2048 KB
fpu		: yes
fpu_exception	: yes
cpuid level	: 5
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 syscall nx lm pni monitor ds_cpl cid cx16 xtpr
bogomips	: 5586.94
clflush size	: 64
cache_alignment	: 128
address sizes	: 36 bits physical, 48 bits virtual
power management:


/proc/meminfo:
MemTotal:      2055920 kB
MemFree:       1529336 kB
Buffers:         69608 kB
Cached:         302556 kB
SwapCached:          0 kB
Active:         150420 kB
Inactive:       287344 kB
HighTotal:           0 kB
HighFree:            0 kB
LowTotal:      2055920 kB
LowFree:       1529336 kB
SwapTotal:     4192956 kB
SwapFree:      4192812 kB
Dirty:            2444 kB
Writeback:           0 kB
Mapped:          85816 kB
Slab:            73896 kB
Committed_AS:   602584 kB
PageTables:       1896 kB
VmallocTotal: 536870911 kB
VmallocUsed:    264960 kB
VmallocChunk: 536605679 kB
HugePages_Total:     0
HugePages_Free:      0
Hugepagesize:     2048 kB

Free space on /tmp at the end= 66292 MiB
End job on node54 at 2009-07-16 05:32:51