#include <cstdio>
#include <map>
using namespace std;

FILE * fin = freopen("hash.in", "r", stdin);
FILE * fout = freopen("hash.out", "w", stdout);

map<int, int> table;
int main()
{
    int i, n, op, x;
    int k = 0;
    scanf("%d", &n);
    for (i = 0; i < n; i++)
    {
        scanf("%d%d", &op, &x);

        switch (op)
        {
        case 1:
            if (table.find(x) == table.end())
                table[x] == ++k;
            break;
        case 2:
            table.erase(x);
            break;
        case 3:
            printf("%d\n", table.find(x) != table.end());
            break;
        }
    }
    return 0;
}