Submission

[PP-SS][SSSSS][SSSSSSSSSS]

Score: 0

User: dwad2

Problemset: ห้องสมุดเมือง 3M

Language: cpp

Time: 0.002 second

Submitted On: 2025-03-20 20:30:25

#include <bits/stdc++.h>

using namespace std;

int main() {
    int n;
    cin >> n;

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

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

    vector<pair<int, int>> merged;
    for (auto [x, y] : libraries) {
        if (merged.empty() || merged.back().second < x) {
            merged.push_back({x, y});
        } else {
            merged.back().second = max(merged.back().second, y);
        }
    }

    long long total_books = 0;
    for (auto [x, y] : merged) {
        total_books += (y - x);
    }

    long long medianIndex = total_books / 2;
    long long count = 0;

    for (auto [x, y] : merged) {
        long long books_in_range = y - x;
        if (count + books_in_range > medianIndex) {
            cout << x + (medianIndex - count) - 1 << endl;
            return 0;
        }
        count += books_in_range;
    }

    return 0;
}