#include <cstdio>
#include <set>
using namespace std;
#define DIM 1000005
int N = 0, v[DIM];
set<int>S;
int main()
{
    int n,type, x;
    FILE *f = fopen("hashuri.in", "r"), *out = fopen("hashuri.out", "w");
    fscanf(f, "%d", &n);
    for (;n;--n)
    {
        fscanf(f, "%d", &type);
        fscanf(f, "%d", &x);
        if (type == 1)
            S.insert(x);
        else
            if (type == 2)
                S.erase(x);
            else
                if (S.find(x) != S.end())
                    fprintf(out, "1\n");
                else
                    fprintf(out, "0\n");


    }

    fclose(f);
    fclose(out);

    return 0;
}