ronak037's blog

How many loops in 1 sec ?
By ronak037, history, 5 years ago, In English

Basically I want to know how many loops we can iterate in 1 sec because according to me this number is approx 10^6 but in ques A of given link: https://mirror.codeforces.com/contest/1341/problem/A, I submitted a solution with brute force by thinking that it takes a maximum of 10^6 loops so I will not tle in system cases but that doesn't happen my solution got tle later and I relook into that solution and also not getting the reason why this solution get tle as it takes a maximum of 10^6 loops. Solution link: https://mirror.codeforces.com/contest/1341/submission/77777541. So please anyone explain to me the reason for this. Thank you

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5 years ago, # |
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  1. Put assertions in your code to check your assumption on the number of loop iterations.
  2. Benchmark your code to check which part is using the most amount of time.
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5 years ago, # |
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There are additional T more loops. So your complexity is O(T*10^6). 10^6 is enough for 1sec but your code runs in 10^6 * 10^3 = 10^9, which is about 10sec.

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    5 years ago, # ^ |
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    I considered T already basically it is O(T*10^3).

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      5 years ago, # ^ |
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      No. (a-b)*n .... (a+b)*n is 10^6. N is 10^3, b is 10^3.

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5 years ago, # |
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In 1 sec we can run a loop doing 1e8 operations. The problem with your code is that as we have t test cases and can have max value of 1000. Suppose you have 1000 test cases so your code can run 1000*( 1000000 ) operations in some cases as 1e9 > 1e8. It will give you TLE.

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