Submission

Score: 0

User: Few500

Problemset: ห้องสมุดเมือง 3M

Language: cpp

Time: 0.002 second

Submitted On: 2026-03-21 19:48:09

#include<iostream>
#include<vector>
#include<algorithm>
using namespace std;

int main(){
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);

    int n;
    cin >> n;
    long long total = 0;
    vector<pair<int, int>> library(n);
    for(int i=0; i<n; i++){
        cin >> library[i].first >> library[i].second;
        total += library[i].second - library[i].first;
    } 

    int l = 0, r = 2e8;
    while(l < r){
        int mid = (l + r) >> 1;
        long long cnt = 0;

        for(auto [start, end] : library){
            if(start <= mid)
                cnt += min(mid, end - 1) - start + 1;
        }

        if(cnt >= total / 2)
            r = mid - 1;
        else
            l = mid + 1;
    }

    cout << l << '\n';
    return 0;
}