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[solved] Strange Memory Limit Exceeded verdict on Kattis?
By bicsi, history, 5 years ago, In English

I was recently trying to solve problem K. Kingdom of Ants on Kattis. However, my submission strangely receives a Memory Limit Exceeded verdict, and I can see no way of achieving that with my code.

Code: https://pastebin.com/0sXQaCdi

Do you guys spot any reasons why the above code would give MLE? Maybe some weird C++ undefined behaviour, or maybe some compiler flaw?

UPDATE: After checking for the (very degenerate) case if there is only one y-coordinate (right between lines 119 and 120), the solution gets Accepted verdict. However, I still don't understand why the initial verdict was MLE, and it was very misleading.

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

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5 years ago, # |
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I think the bug is in initializing the segment tree. It looks like the right bound is initially set to n-2 instead of n-1. The way the init function is defined, this recurses forever instead of RTEing.

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    5 years ago, # ^ |
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    You are right. I posted this before I realized that there can be degenerate rectangles in the input tests. Stack overflow is indeed a reasonable cause of a MLE verdict. I marked the issue as closed.

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