HDU3627 set+map

#include <iostream>
#include <algorithm>
#include <cstring>
#include <cmath>
#include <queue>
#include <vector>
#include <cstdio>
#include <set>
#include <map>
using namespace std;
set<int>s;
set<int>::iterator ss;
map<int,int>y;
map<int,set<int> >f;
map<int,set<int> >::iterator ff;
int main()
{
//freopen("in.txt","r",stdin);
int n,cas=1;
while(~scanf("%d",&n)&&n)
{
if(cas!=1) printf("\n");
s.clear();
y.clear();
f.clear();
char str[10];
int a,b;
printf("Case %d:\n",cas++);
while(n--)
{
scanf("%s%d%d",str,&a,&b);
if(str[0]=='a')
{
if(y.find(b)==y.end()) y[b]=1;
else y[b]++;
if(s.find(a)==s.end()) s.insert(a);
ff=f.find(a);
if(ff==f.end()) f[a].insert(b);
else
{
ss=ff->second.find(b);
if(ss!=ff->second.end()) continue;
ff->second.insert(b);
}
}
else if(str[0]=='f')
{
if(y.upper_bound(b)==y.end())
{
printf("-1\n");
continue;
}
int p=a;
while(1)
{
if(s.empty())
{
printf("-1\n");
break;
}
ss=s.upper_bound(p);
if(ss==s.end())
{
printf("-1\n");
break;
}
else
{
int temp=*ss;
p=temp;
if(f[temp].empty()) continue;
ss=f[temp].upper_bound(b);
if(ss==f[temp].end()) continue;
else
{
printf("%d %d\n",temp,*ss);
break;
}
}
}
}
else if(str[0]=='r')
{
f[a].erase(b);
if(f[a].empty()) s.erase(a);
if(!--y[b]) y.erase(b);
}
}
}
return 0;
}