Why time limited exeeded in my O(nlogn) solution

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Автор Me_iS_NooB, история, 2 года назад, По-английски

i was trying to solve this problem:- https://codeforces.me/contest/1801/problem/B

My solution :- https://codeforces.me/contest/1801/submission/278323418

In my solution i wrote a O(nlogn) solution and the judge is showing time limit exceeded. But in editorial the solution given is O(nlogn) and that is getting passed. I am having trouble understanding how this is happening.

plzz help :,(

Me_iS_NooB
2 года назад
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chocological

2 года назад, скрыть # |

set has its own object function lower_bound to use. Do not use lower_bound in algorithm.h, as performing it on set would most of the time cause an $$$\mathcal{O}(n)$$$ time complexity per call.

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chocological

2 года назад, скрыть # ^ |

Resubmitted but WA: 278326222. Well, since I didn't solve this one yet, I wouldn't give further advice, but at least the TLE is dealt with.

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hossam_osama

2 года назад, скрыть # ^ |

why lower_bound that isn't method in set object act in o(n)

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chocological

2 года назад, скрыть # ^ |

Please refer to this:

However, if ForwardIt is not a LegacyRandomAccessIterator, the number of iterator increments is linear in $$$N$$$.
Notably, std::map, std::multimap, std::set, and std::multiset iterators are not random access, and so their member lower_bound functions should be preferred.