amr0's blog

Maximum of (a[i]+a[j])*(j — i) where j > i
By amr0, history, 4 years ago, In English

Hello Codeforces! I was trying to solve https://codeforces.net/gym/102920/problem/L using divide and conquer. To get the solution that crosses the midpoint I use the observation that the left endpoint, at index i, will be in a monotonically increasing sequence and the right endpoint, at index j, will be in a monotonically decreasing sequence but I get TLE. This is a code snippet from the code I submitted: https://ideone.com/pRWLDD . Your help is appreciated

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4 years ago, # |
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Try the testcase generated by this code:

Generator

Basically, this part of your code can lead N^2 in worst case:

Code

You should understand concept of D&C well to apply it.

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