Submission

Score: 0

User: Ryuthin94

Problemset: ห้องสมุดเมือง 3M

Language: cpp

Time: 0.002 second

Submitted On: 2026-03-04 15:51:58

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

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

    int n;
    cin >> n;

    vector<pair<long long, long long>> ranges(n);
    long long total = 0;

    for (int i = 0; i < n; i++)
    {
        cin >> ranges[i].first >> ranges[i].second;
        total += (ranges[i].second - ranges[i].first);
    }

    if (total == 0)
        return 0;

    long long k = total / 2;

    long long prefix = 0;

    for (int i = 0; i < n; i++)
    {
        long long start = ranges[i].first;
        long long len = ranges[i].second - ranges[i].first;

        if (prefix + len >= k)
        {
            long long value = start + (k - prefix - 1);
            cout << value;
            return 0;
        }

        prefix += len;
    }

    return 0;
}