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why priority_queue is not behaving as expected?
By ToErr, history, 6 years ago, In English

this submission using priority_queue is giving TLE : http://codeforces.net/contest/467/submission/43003735

where using set giving AC : http://codeforces.net/contest/467/submission/43003953

problem link: http://codeforces.net/contest/467/problem/D

could anyone point me out what is wrong here! i am literally not getting the point :(

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6 years ago, # |
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I think you need to check whether not-unique items being inserting into container or not.

set keeps only unique items. priorityqueue doesn't. Therefore you can execute for-loop inside while-loop too many extra times and get TLE.

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    6 years ago, # ^ |
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    yes, thank you for pointing it out.

    it is giving time limit for this 'non-unique' pushing.

    if the edges are like:

    1-x

    2-x

    ...

    ...

    ...

    n-x

    then x will be pushed n times in the queue,which will lead the complexity to O(n^2).

    it is sad that i have missed the point.

    again thank you for pointing this.

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