#include <cstdio>
#include <set>

using namespace std;

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

    set<int> s;

    int n;
    scanf("%d", &n);

    int x, y;

    for(int i = 0; i < n; i++){
        scanf("%d %d", &x, &y);

        switch(x){
        case 1:
            s.insert(y);
            break;
        case 2:
            s.erase(y);
            break;
        case 3:
            if(s.find(y) != s.end()){
                printf("1\n");
            }
            else{
                printf("0\n");
            }
            break;
        }
    }

    return 0;
}