Submission

Score: 0

User: Pung

Problemset: ห้องสมุดเมือง 3M

Language: cpp

Time: 0.002 second

Submitted On: 2026-03-09 08:56:03

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

long long diff[20000005]; 

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

    int n;
    cin >> n;

    int max_val = 0;
    long long K = 0;

    for (int i = 0; i < n; i++) {
        int x, y;
        cin >> x >> y; 
        diff[x]++;   
        diff[y]--;    
        K += (y - x); 
        if (y > max_val) max_val = y;
    }

    int target = K / 2; 
    long long current_books = 0;
    long long active_intervals = 0;

    for (int i = 0; i <= max_val; i++) {
        active_intervals += diff[i];
        
    
        if (current_books + active_intervals >= target) {
            cout << i;
            return 0;
        }
        current_books += active_intervals;
    }

    return 0;
}