#include <bits/stdc++.h>

using namespace std;

int N, tip, x;
unordered_set<int> h;

int main(){

    freopen("hashuri.in", "r", stdin);
    freopen("hashuri.out", "w", stdout);

    scanf("%d", &N);
    for(int i = 0; i < N; i++){
        scanf("%d%d", &tip, &x);
        if(tip==1 && h.find(x) == h.end())
            h.insert(x);
        else if(tip==2)
            h.erase(x);
        else h.find(x) == h.end() ? printf("0\n") : printf("1\n");
    }

    return 0;
}