#include <cstdio>
#include <unordered_map>
#define DIM 3666013

using namespace std;

unordered_map<int,int> H;

char buffer[DIM];
int poz = DIM - 1;

void Scanf(int &A){
    A = 0;
    while('0' > buffer[poz] || buffer[poz] > '9')
        if(++poz == DIM)
            fread(buffer,1,DIM,stdin),poz = 0;
    while('0' <= buffer[poz] && buffer[poz] <= '9')
    {
        A = A * 10 + buffer[poz] - 48;
        if(++poz == DIM)
            fread(buffer,1,DIM,stdin),poz = 0;
    }
}

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

    int N,op,x;
    Scanf(N);
    for(auto i = 1; i <= N; ++i)
    {
        Scanf(op);
        Scanf(x);
        if(op == 1)
            H[x] = 1;
        else
            if(op == 2)
                H[x] = 0;
            else
                printf("%d\n",H[x]);
    }

    return 0;
}