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Question: When to avoid square root decomposition?
By usernameson, history, 8 years ago, In English

Are there any good rules of thumb on when a square root decomposition will be too slow? I suspect if we have an interval of length 105 and 3 × 105 queries a square root decomposition is too slow but this is only based on my attempts to solve http://codeforces.net/problemset/problem/765/F with a square root decomposition where I calculated the complexity of my algorithm to be and exceeding the time limit. In general if you are given an interval of length N and Q queries what sort of values of do you want in order to be confident that a square root decomposition will pass the time constraint? Also are there standard limits used in Codeforces deliberately set to prevent square root decomposition based approaches?

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8 years ago, # |
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Auto comment: topic has been updated by usernameson (previous revision, new revision, compare).

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8 years ago, # |
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Is it really ever possible to be confident in square root decomposition?

Probably as long as complexity yield less than 200m operations you are fine.

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    8 years ago, # ^ |
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    Thanks I will use 200m operations as a rule of thumb for future problems.

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