Yen_Nhi's blog

Am I stupid or sth?
By Yen_Nhi, history, 8 months ago, In English

So I tried problem G on the last div3 contest, my solution seems to work with small test case but then gave me an TLE with bigger test case

My submission : https://mirror.codeforces.com/contest/1941/submission/251046117

Problem's statement : https://mirror.codeforces.com/contest/1941/problem/G

UPD : sorry my dijkstra implementation was wrong :v

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8 months ago, # |
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It's said that there are $$$2 \cdot 10^5$$$ vertexes, $$$2 \cdot 10^5$$$ edges and also $$$2 \cdot 10^5$$$ colors. Your code's time complexity at least is $$$O(NC)$$$ where $$$C$$$ is the count of colors.

And, priority_queue is not necessary.

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    8 months ago, # ^ |
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    I think that the second dimension of the map only contains the color of edges that can go to that vertex

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8 months ago, # |
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No, I am Ac in contest but still TLE in test 47 after hacking 250934676, I think some one had rand a test anti prioryty_queue.

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

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8 months ago, # |
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As far as I see from the code, for each pair (vertex v, color c) you traverse all edges incident to v. So basically if there is a vertex with all m edges incident to it and all have different colors, you will do at least O(m^2) operations, which is clear TLE.

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