https://codeforces.net/problemset/problem/498/B

For the above question, this was my TLE solution : 55865422 : time=1000ms

and this was my Accepted solution : [submission:55865596] : time=155ms

In TLE solution, i just added one line: if( dp[i][j] < (1e-12) ) dp[i][j]=0;

and it got accepted.

I am not able to understand that how this one line is able to reduce the time complexity ( and also by such huge margin ) as it is not involved in any of the loops.