#include <bits/stdc++.h>

using namespace std;
map <int,int> m;
int nr;
int main()
{
    freopen("hashuri.in", "r", stdin);
	freopen("hashuri.out", "w", stdout);
    int n,x,y;
    cin>>n;
    for(int i=1;i<=n;i++){
        cin>>x>>y;
        switch(x){
        case 1:
            if(m.find(y)==m.end())
                m[y]=++nr;
            break;
        case 2:
            m.erase(y);
            break;
        case 3:
                cout<<(m.find(y)!=m.end())<<"\n";
            break;
        }
    }
    return 0;
}