#include <cstdio>
#include <unordered_set>
using namespace std;
int n,c,v;
unordered_set<int> T;
int main()
{
    freopen("hashuri.in","r",stdin);
    freopen("hashuri.out","w",stdout);
    scanf("%d",&n);
    for(;n;n--)
    {
        scanf("%d%d",&c,&v);
        if(c==1)
            T.insert(v);
        else
            if(c==2)
                T.erase(v);
                else
                    T.find(v)==T.end()? printf("0\n"):printf("1\n");
    }
    return 0;
}