Submission

Score: 100

User: syndrxme

Problemset: วันว่างๆ

Language: cpp

Time: 0.020 second

Submitted On: 2026-03-14 09:24:50

#include<bits/stdc++.h>
using namespace std;
int main(){
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);
    int n;
    cin>>n;
    vector<pair<int,int>> event;
    for(int i=0;i<n;i++){
        int m;
        cin>>m;
        for(int j=0;j<m;j++){
            int s,e;
            cin>>s>>e;
            event.push_back({s,-1});
            event.push_back({e,1});
        }
    }
    sort(event.begin(), event.end());
    // for(auto& c:event){
    //     cout<<c.first<<" "<<c.second<<endl;
    // }
    int nowbusy=0;
    int last=-1;
    vector<pair<int,int>> ans;
    for(auto& e:event){
        int curtime = e.first;
        int type = e.second;

        if(nowbusy==0 && type==-1 && last!=-1){
            if(curtime>last){
                ans.push_back({last,curtime});
            }
        }

        if(type==-1){
            nowbusy++;
        }else{
            nowbusy--;
        }
        if(nowbusy==0){
            last = curtime;
        }
    }
    if(ans.empty()==true){
        cout<<-1;
    }else{
        for(auto& p:ans){
            cout<<p.first<<" "<<p.second<<" ";
        }
    }
    return 0;
}