Trace number 1518713

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
VARSAT-random 2009-03-22SAT 52.1411 52.1547

General information on the benchmark

NameRANDOM/MEDIUM/3SAT/SATISFIABLE/440/
unif-k3-r4.25-v440-c1870-S725789261-031.cnf
MD5SUMf67f090e24644066ce5872fbc256498a
Bench CategoryRANDOM (random instances)
Best result obtained on this benchmarkSAT
Best CPU time to get the best result obtained on this benchmark0.011997
Satisfiable
(Un)Satisfiability was proved
Number of variables440
Number of clauses1870
Sum of the clauses size5610
Maximum clause length3
Minimum clause length3
Number of clauses of size 10
Number of clauses of size 20
Number of clauses of size 31870
Number of clauses of size 40
Number of clauses of size 50
Number of clauses of size over 50

Solver Data 

0.00/0.00	c ============================[ Problem Statistics ]=============================
0.00/0.00	c |                                                                             |
0.00/0.00	c |  Number of variables:  440                                                  |
0.00/0.00	c |  Number of clauses:    1870                                                 |
0.00/0.00	c |  Parsing time:         0.00         s                                       |
0.00/0.00	c |  Timeout:              43200 s
0.00/0.00	c |  Random Seed:          777337896.000000
0.00/0.00	c |  Heuristic:            EMSP-G, threshold 0.750                              |
0.00/0.00	c |  Branching Rule:       default (solution-guided)                            |
0.00/0.00	c |  Learned clauses in surveys?  Using NO learned clauses.                     |
0.00/0.00	c |                                                                             |
0.00/0.00	c ============================[ Search Statistics ]==============================
0.00/0.00	c | Conflicts |          ORIGINAL         |          LEARNT          | Progress |
0.00/0.00	c |           |    Vars  Clauses Literals |    Limit  Clauses Lit/Cl |          |
0.00/0.00	c ===============================================================================
0.00/0.00	c |         0 |     426     1844     5596 |      614        0    nan |  0.000 % |
0.01/0.02	c |       102 |     426     1844     5596 |      676      102     21 |  0.001 % |
0.01/0.04	c |       253 |     426     1844     5596 |      743      253     22 |  0.001 % |
0.01/0.07	c |       481 |     426     1844     5596 |      818      481     23 |  0.001 % |
0.01/0.09	c |       818 |     426     1844     5596 |      899      818     22 |  0.001 % |
0.09/0.13	c |      1324 |     426     1844     5596 |      989      841     21 |  0.001 % |
0.09/0.17	c |      2083 |     426     1844     5596 |     1088      575     18 |  0.001 % |
0.19/0.23	c |      3223 |     426     1844     5596 |     1197     1147     20 |  0.001 % |
0.29/0.32	c |      4932 |     426     1844     5596 |     1317      981     20 |  0.001 % |
0.39/0.44	c |      7495 |     426     1844     5596 |     1449      794     20 |  0.001 % |
0.59/0.62	c |     11341 |     426     1844     5596 |     1594      897     19 |  0.001 % |
0.79/0.90	c |     17108 |     426     1844     5596 |     1753      916     20 |  0.001 % |
1.29/1.30	c |     25757 |     426     1844     5596 |     1929     1441     21 |  0.001 % |
1.89/1.92	c |     38732 |     426     1844     5596 |     2121     1572     21 |  0.001 % |
2.79/2.88	c |     58194 |     426     1844     5596 |     2334     1503     20 |  0.001 % |
4.30/4.39	c |     87388 |     426     1844     5596 |     2567     2037     23 |  0.001 % |
6.59/6.67	c |    131178 |     426     1844     5596 |     2824     2532     23 |  0.001 % |
10.19/10.22	c |    196862 |     426     1844     5596 |     3106     2039     21 |  0.001 % |
15.69/15.70	c |    295389 |     426     1844     5596 |     3417     2542     23 |  0.001 % |
24.29/24.31	c |    443178 |     426     1844     5596 |     3759     2736     23 |  0.001 % |
37.59/37.66	c |    664863 |     426     1844     5596 |     4135     3522     23 |  0.001 % |
52.08/52.15	c ===============================================================================
52.08/52.15	c surveys--CPU time (sec)   : 0.3529         (0.68 % of total)
52.08/52.15	c surveys--attempted        : 147            (416 /sec)
52.08/52.15	c surveys--converged        : 147            (100.00 % successful)
52.08/52.15	c restarts              : 21
52.08/52.15	c conflicts             : 895721         (17300 /sec)
52.08/52.15	c decisions             : 1076299        (1.77 % random) (20788 /sec)
52.08/52.15	c propagations          : 57830600       (1116936 /sec)
52.08/52.15	c conflict literals     : 23212152       (16.02 % deleted)
52.08/52.15	c Memory used           : 4.93 MB
52.08/52.15	c Total CPU time (sec)      : 52.1291     
52.08/52.15	c 
52.08/52.15	s SATISFIABLE
52.08/52.15	v -1 -2 -3 -4 -5 -6 7 -8 9 -10 11 12 -13 -14 15 16 -17 -18 19 20 -21 22 23 24 -25 26 -27 -28 -29 30 31 32 33 -34 35 -36 37 -38 39 40 -41 42 -43 -44 -45 46 47 -48 -49 -50 -51 -52 53 -54 -55 56 57 -58 -59 60 -61 -62 -63 64 -65 -66 -67 -68 69 70 71 -72 -73 74 75 -76 -77 78 79 80 -81 -82 -83 84 -85 -86 -87 -88 -89 90 91 92 93 -94 95 -96 97 98 99 100 101 -102 103 -104 -105 106 -107 108 -109 -110 -111 -112 -113 -114 -115 -116 -117 -118 -119 -120 121 -122 -123 -124 -125 -126 127 -128 129 -130 -131 -132 133 -134 -135 -136 -137 -138 -139 140 -141 142 143 144 -145 146 -147 148 149 150 151 -152 153 -154 -155 156 -157 158 159 160 161 162 -163 164 165 166 -167 -168 -169 170 -171 -172 173 174 175 -176 -177 -178 179 180 -181 -182 183 184 -185 186 187 -188 -189 190 -191 192 193 -194 195 196 197 -198 199 -200 -201 -202 203 204 -205 -206 -207 208 -209 210 211 -212 213 -214 -215 -216 -217 218 -219 -220 221 222 -223 224 -225 226 -227 228 -229 230 231 -232 -233 -234 235 236 -237 -238 239 240 -241 242 243 244 245 246 -247 -248 249 250 251 252 -253 -254 255 256 -257 -258 -259 260 261 262 -263 -264 -265 -266 267 268 -269 -270 -271 -272 273 274 275 276 277 -278 -279 280 -281 282 283 -284 285 -286 287 288 -289 -290 -291 -292 293 294 295 296 -297 298 -299 300 301 -302 303 -304 -305 306 307 -308 -309 310 311 312 313 314 -315 -316 317 318 -319 -320 -321 -322 -323 324 325 -326 327 -328 329 -330 331 332 333 -334 335 336 -337 338 -339 -340 341 342 -343 344 -345 346 347 348 -349 -350 351 -352 353 354 -355 -356 357 358 -359 -360 361 -362 363 -364 -365 366 367 368 -369 370 -371 -372 373 374 375 -376 -377 378 379 380 -381 -382 -383 384 385 386 387 -388 -389 390 -391 392 -393 -394 395 -396 -397 398 399 400 401 -402 -403 404 405 -406 407 -408 -409 -410 -411 -412 -413 -414 -415 -416 -417 418 -419 -420 -421 -422 423 -424 -425 426 -427 428 -429 430 431 432 -433 -434 -435 -436 437 -438 -439 -440 0

Verifier Data 

OK

Watcher Data 

runsolver version 3.2.9 (svn:489) (c) roussel@cril.univ-artois.fr

command line: BIN/runsolver --timestamp -w /tmp/evaluation-result-1518713-1238303143/watcher-1518713-1238303143 -o /tmp/evaluation-result-1518713-1238303143/solver-1518713-1238303143 -C 1200 -W 1800 -M 1800 --output-limit 1,15 HOME/varsat-random_static -seed=777337896 HOME/instance-1518713-1238303143.cnf 

Enforcing CPUTime limit (soft limit, will send SIGTERM then SIGKILL): 1200 seconds
Enforcing CPUTime limit (hard limit, will send SIGXCPU): 1230 seconds
Enforcing wall clock limit (soft limit, will send SIGTERM then SIGKILL): 1800 seconds
Enforcing VSIZE limit (soft limit, will send SIGTERM then SIGKILL): 1843200 KiB
Enforcing VSIZE limit (hard limit, stack expansion will fail with SIGSEGV, brk() and mmap() will return ENOMEM): 1894400 KiB
Solver output will be limited to a maximum of 15728640 bytes. The first 1048576 bytes and the last 14680064 bytes will be preserved
Current StackSize limit: 10240 KiB


[startup+0 s]
/proc/loadavg: 0.92 0.98 0.99 3/64 24039
/proc/meminfo: memFree=822752/2055920 swapFree=4172472/4192956
[pid=24039] ppid=24037 vsize=2416 CPUtime=0
/proc/24039/stat : 24039 (varsat-random_s) R 24037 24039 23686 0 -1 4194304 225 0 0 0 0 0 0 0 18 0 1 0 1102977550 2473984 210 1992294400 4194304 5102416 548682068800 18446744073709551615 4490012 0 0 4096 3 0 0 0 17 1 0 0
/proc/24039/statm: 604 210 98 221 0 380 0

[startup+0.0181661 s]
/proc/loadavg: 0.92 0.98 0.99 3/64 24039
/proc/meminfo: memFree=822752/2055920 swapFree=4172472/4192956
[pid=24039] ppid=24037 vsize=2520 CPUtime=0.01
/proc/24039/stat : 24039 (varsat-random_s) R 24037 24039 23686 0 -1 4194304 237 0 0 0 1 0 0 0 18 0 1 0 1102977550 2580480 222 1992294400 4194304 5102416 548682068800 18446744073709551615 4220281 0 0 4096 3 0 0 0 17 1 0 0
/proc/24039/statm: 630 222 102 221 0 406 0
Current children cumulated CPU time (s) 0.01
Current children cumulated vsize (KiB) 2520

[startup+0.101175 s]
/proc/loadavg: 0.92 0.98 0.99 3/64 24039
/proc/meminfo: memFree=822752/2055920 swapFree=4172472/4192956
[pid=24039] ppid=24037 vsize=2520 CPUtime=0.09
/proc/24039/stat : 24039 (varsat-random_s) R 24037 24039 23686 0 -1 4194304 251 0 0 0 9 0 0 0 18 0 1 0 1102977550 2580480 236 1992294400 4194304 5102416 548682068800 18446744073709551615 4220145 0 0 4096 3 0 0 0 17 1 0 0
/proc/24039/statm: 630 236 112 221 0 406 0
Current children cumulated CPU time (s) 0.09
Current children cumulated vsize (KiB) 2520

[startup+0.301195 s]
/proc/loadavg: 0.92 0.98 0.99 3/64 24039
/proc/meminfo: memFree=822752/2055920 swapFree=4172472/4192956
[pid=24039] ppid=24037 vsize=2652 CPUtime=0.29
/proc/24039/stat : 24039 (varsat-random_s) R 24037 24039 23686 0 -1 4194304 281 0 0 0 29 0 0 0 19 0 1 0 1102977550 2715648 266 1992294400 4194304 5102416 548682068800 18446744073709551615 4255180 0 0 4096 3 0 0 0 17 1 0 0
/proc/24039/statm: 663 266 112 221 0 439 0
Current children cumulated CPU time (s) 0.29
Current children cumulated vsize (KiB) 2652

[startup+0.701239 s]
/proc/loadavg: 0.92 0.98 0.99 3/64 24039
/proc/meminfo: memFree=822752/2055920 swapFree=4172472/4192956
[pid=24039] ppid=24037 vsize=2784 CPUtime=0.69
/proc/24039/stat : 24039 (varsat-random_s) R 24037 24039 23686 0 -1 4194304 323 0 0 0 69 0 0 0 22 0 1 0 1102977550 2850816 308 1992294400 4194304 5102416 548682068800 18446744073709551615 4249721 0 0 4096 3 0 0 0 17 1 0 0
/proc/24039/statm: 696 308 112 221 0 472 0
Current children cumulated CPU time (s) 0.69
Current children cumulated vsize (KiB) 2784

[startup+1.50133 s]
/proc/loadavg: 0.92 0.98 0.99 2/65 24040
/proc/meminfo: memFree=821784/2055920 swapFree=4172472/4192956
[pid=24039] ppid=24037 vsize=2916 CPUtime=1.49
/proc/24039/stat : 24039 (varsat-random_s) R 24037 24039 23686 0 -1 4194304 364 0 0 0 149 0 0 0 25 0 1 0 1102977550 2985984 349 1992294400 4194304 5102416 548682068800 18446744073709551615 4249573 0 0 4096 3 0 0 0 17 1 0 0
/proc/24039/statm: 729 349 112 221 0 505 0
Current children cumulated CPU time (s) 1.49
Current children cumulated vsize (KiB) 2916

[startup+3.1015 s]
/proc/loadavg: 0.92 0.98 0.99 2/65 24040
/proc/meminfo: memFree=821464/2055920 swapFree=4172472/4192956
[pid=24039] ppid=24037 vsize=3180 CPUtime=3.09
/proc/24039/stat : 24039 (varsat-random_s) R 24037 24039 23686 0 -1 4194304 430 0 0 0 309 0 0 0 25 0 1 0 1102977550 3256320 415 1992294400 4194304 5102416 548682068800 18446744073709551615 4249451 0 0 4096 3 0 0 0 17 1 0 0
/proc/24039/statm: 795 415 112 221 0 571 0
Current children cumulated CPU time (s) 3.09
Current children cumulated vsize (KiB) 3180

[startup+6.30185 s]
/proc/loadavg: 0.93 0.98 0.99 2/65 24040
/proc/meminfo: memFree=821080/2055920 swapFree=4172472/4192956
[pid=24039] ppid=24037 vsize=3444 CPUtime=6.29
/proc/24039/stat : 24039 (varsat-random_s) R 24037 24039 23686 0 -1 4194304 497 0 0 0 629 0 0 0 25 0 1 0 1102977550 3526656 482 1992294400 4194304 5102416 548682068800 18446744073709551615 4249655 0 0 4096 3 0 0 0 17 1 0 0
/proc/24039/statm: 861 482 112 221 0 637 0
Current children cumulated CPU time (s) 6.29
Current children cumulated vsize (KiB) 3444

[startup+12.7015 s]
/proc/loadavg: 0.93 0.98 0.99 2/65 24040
/proc/meminfo: memFree=820576/2055920 swapFree=4172472/4192956
[pid=24039] ppid=24037 vsize=3840 CPUtime=12.69
/proc/24039/stat : 24039 (varsat-random_s) R 24037 24039 23686 0 -1 4194304 593 0 0 0 1269 0 0 0 25 0 1 0 1102977550 3932160 578 1992294400 4194304 5102416 548682068800 18446744073709551615 4254417 0 0 4096 3 0 0 0 17 1 0 0
/proc/24039/statm: 960 578 112 221 0 736 0
Current children cumulated CPU time (s) 12.69
Current children cumulated vsize (KiB) 3840

[startup+25.5019 s]
/proc/loadavg: 0.95 0.98 0.99 2/65 24040
/proc/meminfo: memFree=820064/2055920 swapFree=4172472/4192956
[pid=24039] ppid=24037 vsize=4376 CPUtime=25.49
/proc/24039/stat : 24039 (varsat-random_s) R 24037 24039 23686 0 -1 4194304 720 0 0 0 2548 1 0 0 25 0 1 0 1102977550 4481024 705 1992294400 4194304 5102416 548682068800 18446744073709551615 4249655 0 0 4096 3 0 0 0 17 1 0 0
/proc/24039/statm: 1094 705 112 221 0 870 0
Current children cumulated CPU time (s) 25.49
Current children cumulated vsize (KiB) 4376

[startup+51.1017 s]
/proc/loadavg: 0.96 0.98 0.99 2/65 24040
/proc/meminfo: memFree=819488/2055920 swapFree=4172472/4192956
[pid=24039] ppid=24037 vsize=5048 CPUtime=51.08
/proc/24039/stat : 24039 (varsat-random_s) R 24037 24039 23686 0 -1 4194304 873 0 0 0 5107 1 0 0 25 0 1 0 1102977550 5169152 858 1992294400 4194304 5102416 548682068800 18446744073709551615 4253879 0 0 4096 3 0 0 0 17 1 0 0
/proc/24039/statm: 1262 858 112 221 0 1038 0
Current children cumulated CPU time (s) 51.08
Current children cumulated vsize (KiB) 5048

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

[startup+51.9018 s]
/proc/loadavg: 0.96 0.98 0.99 2/65 24040
/proc/meminfo: memFree=819424/2055920 swapFree=4172472/4192956
[pid=24039] ppid=24037 vsize=5048 CPUtime=51.88
/proc/24039/stat : 24039 (varsat-random_s) R 24037 24039 23686 0 -1 4194304 885 0 0 0 5187 1 0 0 25 0 1 0 1102977550 5169152 870 1992294400 4194304 5102416 548682068800 18446744073709551615 4248793 0 0 4096 3 0 0 0 17 1 0 0
/proc/24039/statm: 1262 870 112 221 0 1038 0
Current children cumulated CPU time (s) 51.88
Current children cumulated vsize (KiB) 5048

[startup+52.1018 s]
/proc/loadavg: 0.96 0.98 0.99 2/65 24040
/proc/meminfo: memFree=819424/2055920 swapFree=4172472/4192956
[pid=24039] ppid=24037 vsize=5048 CPUtime=52.08
/proc/24039/stat : 24039 (varsat-random_s) R 24037 24039 23686 0 -1 4194304 885 0 0 0 5207 1 0 0 25 0 1 0 1102977550 5169152 870 1992294400 4194304 5102416 548682068800 18446744073709551615 4249721 0 0 4096 3 0 0 0 17 1 0 0
/proc/24039/statm: 1262 870 112 221 0 1038 0
Current children cumulated CPU time (s) 52.08
Current children cumulated vsize (KiB) 5048

Child status: 10
Real time (s): 52.1547
CPU time (s): 52.1411
CPU user time (s): 52.1291
CPU system time (s): 0.011998
CPU usage (%): 99.9739
Max. virtual memory (cumulated for all children) (KiB): 5048

getrusage(RUSAGE_CHILDREN,...) data:
user time used= 52.1291
system time used= 0.011998
maximum resident set size= 0
integral shared memory size= 0
integral unshared data size= 0
integral unshared stack size= 0
page reclaims= 890
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= 2
involuntary context switches= 70

runsolver used 0.044993 second user time and 0.117982 second system time

The end

Launcher Data 

Begin job on node37 at 2009-03-29 07:05:43
IDJOB=1518713
IDBENCH=70702
IDSOLVER=539
FILE ID=node37/1518713-1238303143
PBS_JOBID= 9061031
Free space on /tmp= 66424 MiB

SOLVER NAME= VARSAT-random 2009-03-22
BENCH NAME= SAT09/RANDOM/MEDIUM/3SAT/SATISFIABLE/440/unif-k3-r4.25-v440-c1870-S725789261-031.cnf
COMMAND LINE= HOME/varsat-random_static -seed=RANDOMSEED BENCHNAME
RUNSOLVER COMMAND LINE= BIN/runsolver --timestamp -w /tmp/evaluation-result-1518713-1238303143/watcher-1518713-1238303143 -o /tmp/evaluation-result-1518713-1238303143/solver-1518713-1238303143 -C 1200 -W 1800 -M 1800 --output-limit 1,15  HOME/varsat-random_static -seed=777337896 HOME/instance-1518713-1238303143.cnf

TIME LIMIT= 1200 seconds
MEMORY LIMIT= 1800 MiB
MAX NB THREAD= 0

MD5SUM BENCH= f67f090e24644066ce5872fbc256498a
RANDOM SEED=777337896

node37.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		: 3000.213
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		: 3000.213
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:        823168 kB
Buffers:        106232 kB
Cached:        1018292 kB
SwapCached:      14544 kB
Active:         363804 kB
Inactive:       776720 kB
HighTotal:           0 kB
HighFree:            0 kB
LowTotal:      2055920 kB
LowFree:        823168 kB
SwapTotal:     4192956 kB
SwapFree:      4172472 kB
Dirty:            1268 kB
Writeback:           0 kB
Mapped:          18764 kB
Slab:            78316 kB
Committed_AS:  2806532 kB
PageTables:       1384 kB
VmallocTotal: 536870911 kB
VmallocUsed:    264952 kB
VmallocChunk: 536605679 kB
HugePages_Total:     0
HugePages_Free:      0
Hugepagesize:     2048 kB

Free space on /tmp at the end= 66424 MiB
End job on node37 at 2009-03-29 07:06:36