Submission

Score: 100

User: mightbeputter

Problemset: วันว่างๆ

Language: cpp

Time: 0.014 second

Submitted On: 2026-03-27 14:15:59

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

map<int, int> mp;

int main(){
    cin.tie(nullptr)->sync_with_stdio(false);
    int n;
    cin >> n;
    for(int i=1;i<=n;i++){
        int m;
        cin >> m;
        for(int j=1;j<=m;j++){
            int st,en;
            cin >> st >> en;
            mp[st] += 1;
            mp[en] += -1;
        }
    }
    int last = -1, cnt = 0;
    bool ch = false;
    for(auto& x : mp){
        if(cnt == 0 && last != -1) cout << last << " " << x.first << " ", ch = true;
        last = x.first;
        cnt += x.second;
    }
    if(!ch) cout << "-1";
    return 0;
}