Submission

Score: 0

User: tHeNyXs

Problemset: ห้องสมุดเมือง 3M

Language: cpp

Time: 0.003 second

Submitted On: 2026-03-06 20:37:59

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

int main(){
    ios::sync_with_stdio(false);
    cin.tie(nullptr);

    int n; cin >> n;

    vector<pair<int,int>> ev;
    ll total = 0;

    for(int i=0;i<n;i++){
        int x,y; cin >> x >> y;
        ev.push_back({x,1});
        ev.push_back({y,-1});
        total += y-x;
    }

    sort(ev.begin(),ev.end());

    ll mid = total/2;
    ll active = 0;

    for(int i=0;i<ev.size()-1;i++){
        active += ev[i].second;

        ll len = (ll)active * (ev[i+1].first - ev[i].first);

        if(mid <= len){
            cout << ev[i].first + mid/active;
            return 0;
        }

        mid -= len;
    }
}