Variation in running times

Why is there so much variation in running time with the same code. 68181989 and 68150808 uses same code, TLE’d during contest and is now AC’ing with 0.13 ms margin. Same thing happened in last lunchtime too with 67204134 and 67134019 . I don’t think this should be the intended behaviour.

“The other factor is the execution time fluctuations. No two machines are exactly the same, and even in the same machine, the environment during two different runs is also not exactly the same. We try our best to configure the machines and provide as uniform an environment as possible, but even with those, multiple runs of the same code can take slightly different times to run. These changes are pretty small and in the range of tenths of a second difference. This has not been an issue for us with the old checkers, except for some very rare cases. Our tests show that even with the new checkers, the execution times are pretty consistent, but the range could be slightly larger than with the old checkers. We expect the execution times to be within +/- 13% difference. That is, if a code runs in 1 second, on running it many times, the different execution times might go up to 1.13 seconds sometimes, and similarly lower.”

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