#include <bits/stdc++.h>

using namespace std;
unordered_map<string,bool> m;
ifstream in("hashuri.in");
ofstream out("hashuri.out");
int main(){
    int n;
    in>>n;
    for(;n;n--){
        char c;
        string x;
        in>>c>>x;
        if(c=='1')m[x]=1;
        else if(c=='2')m.erase(x);
        else {out<<m[x]<<'\n';if(!m[x])m.erase(x);}
    }
}