stanislav.bezkorovainyi's blog

Strange MLE
By stanislav.bezkorovainyi, history, 6 years ago, In English

I got two solutions for http://codeforces.net/contest/1036/problem/F

First one: 42893786 Second one: 42893945

First solution gets MLE, though it differs from second one only in line 81. On this line in first approach I try to use precalculated values from the array, instead of calculating them anew.

Can someone explain how a person can get MLE because of trying to get a value from an array?

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6 years ago, # |
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In C++, this is normally due to an assert statement in C++ not returning true, but some STL elements can generate this if they try to store too much memory.

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    6 years ago, # ^ |
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    If I erase the assert statement it still does not work.

    As I told you, memory consumption by arrays/STL containers are the same in both of my solutions. It is only line 81 that matters where I try to get value from j-th elemnt of the array.

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6 years ago, # |
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I think that compiler can decrease the size of an array or remove it completely, if it understands that it will not be used.

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    6 years ago, # ^ |
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    It is not the case here, because in my second 42893945 solution I both multiply the elements of the array and push_back them into the vector, so the array is actively used, but there is no MLE.

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