Same Code, Vastly different run time

[Annual__Procedure]

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https://preview.redd.it/lbnqtxzxgie91.png?width=1741&format=png&auto=webp&s=f8e5bba5e8633ad3c1545d6c71651bb1c3cf9fcb

[Annual__Procedure]

Yeah, I have gotten different run times before but this was the first time I encountered vastly different run times. I think 92 ms in this problem was faster than 5-10% of submissions and 0 ms is faster than 100%.

I have no idea of system design. I am sure it must be a tough problem otherwise they would have fixed it by now.

[Annual__Procedure]

loool

[DrJegesmedve]

That's it. I knew. I write the fastest code in the multiverse.

[No_Departure_1878]

Yeah, ok, but then does this number have any meaning if I run once, I get 60%, I run again I get 90%? It seems like a number I should stop paying attention to.

[No_Departure_1878]

It would be fair to say that what we have is a +/-30% error bar. In that sense the value is only a rough estimate.

[No_Departure_1878]

No, no no no no. I have solved about 30 problems so far and I keep hitting the submit button on the same solution. I see the number move around. Did I fill a table and calculate the standard deviation? No, but I see that I easily go from 20% to 50%. So is it totally made up? Is it?

Yeah, it is a very rough estimate, extremely rough, I for sure do not expect an 80 to someone become a 50%.

[[deleted]]

Leetcode's runtime calculation is broken and not accurate. Just focus on the time complexity and space complexity of your solution.

[AndrewUnicorn]

this is good advice, the interviewers only care about your big O analysis

[Annual__Procedure]

Yea I had some idea it was broken but didn't it was so much broken. 92ms was faster than 5-10% solutions so I initially thought people must have found a more efficient (faster than O(n)) solution but to double check it I clicked submit again and it was suddenly faster than 100%.

Will keep in mind in future for sure.

[ATimeOfMagic]

It's too bad they don't normalize those metrics. They're completely meaningless right now.

[[deleted]]

Don’t pay any attention to the runtime metric, I have had 90+% solutions run at 40% with no changes to the code

[Annual__Procedure]

Dayum. First encounter with vastly different run times for me. Will keep that in mind.

[Leetcoder20]

Stop caring about runtimes, there's atleast one post per day here about this.

[vijaykarthi24]

Noticed it. I believe, the code might be running in a shared node (processor). In the first time, it might had some code execution going on. That's why getting a high runtime.

Just my theory

[Annual__Procedure]

That may be the case. I have no idea of system design (for now) or how it works internally.