set 用法
#include <bits/stdc++.h>
using namespace std;
int main()
{pair<int,int >p;int n;char str[10];int c=1;while(cin>>n&&n){cout<<"Case "<<c++<<":"<<endl;set< pair<int,int> >s;while(n--){scanf("%s%d%d",str,&p.first,&p.second);if(str[0]=='a')s.insert(p);else if(str[0]=='r')s.erase(p);else if(str[0]=='f'){set< pair<int,int> >::iterator it;it=s.lower_bound(p);for(;it!=s.end();it++){if(it->first > p.first && it->second > p.second){cout<<it->first <<" " << it->second <<endl;break;}}if(it==s.end()) cout<<-1<<endl;}}puts("");}return 0;
}