saadamin2006's blog

Trying to figure out why my solution TLEs
By saadamin2006, history, 5 months ago, In English

Hello y'all! I'm new to Codeforces and I am trying to solve this 1974F

Here is my submission. My approach is to sort the points by the x- and y-axes and use a two pointers approach that slowly closes in on the grid to find the answer. My analysis says my solution should run in O(nlogn + n + m) time, but it appears to TLE on test 7 and takes quite a while for smaller inputs.

Is cache efficiency the reason here? My algorithm is pretty cache inefficient, but cache efficiency feels more like a constant-time optimization that wouldn't really impact an algorithm that TLEs. What are your thoughts on this?

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5 months ago, # |
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Auto comment: topic has been updated by saadamin2006 (previous revision, new revision, compare).

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5 months ago, # |
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In the lambda expression used for sorting, you are capturing chips by value. This causes the entire vector to be copied for each comparison. Capturing by reference should fix this issue.

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