Submission

[PPPPP][PPPPP][PPPPPPPPPP]

Score: 100

User: Cmoss9

Problemset: ห้องสมุดเมือง 3M

Language: cpp

Time: 0.009 second

Submitted On: 2025-03-23 17:13:53

#include <bits/stdc++.h>
using namespace std;

int main () {
    ios_base::sync_with_stdio(0); cin.tie(NULL);
    int n;
    cin >> n;
    vector<pair<int,int>> books;
    int sum = 0;
    for (int i = 0;i<n;i++) {
        int a,b;
        cin >> a >> b;
        books.push_back({a,1});
        books.push_back({b,-1});
        sum += b-a;
    }
    sort(books.begin(), books.end());
    int median = sum/2;
    int index = 0;
    int lvl = 0;
    int count = 0;
    while (true) {
        int current = books[index].first;
        while (current == books[index].first) {
            int value = books[index].second;
            lvl += value;
            index++;
        }
        while (current < books[index].first) {
            count += lvl;
            if (count >= median) {
                cout << current;
                return 0;
            }
            current++;
        }
    }
}