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

int main()
{
    freopen("hashuri.in","r",stdin);
    freopen("hashuri.out","w",stdout);
    int n ,op,x;
    scanf("%d",&n);
    set<int>v;
    for(int i=0;i<n;i++)
    {
        scanf("%d%d",&op,&x);
        if(op==1)
        {
            v.insert(x);
            continue;
        }
        if(op==2)
        {
            v.erase(x);
            continue;
        }
        if(op==3)
        {
            set<int>::iterator it;
            it=v.find(x);
            if(it!=v.end())printf("1\n");
            else
                printf("0\n");
        }
    }
    return 0;
}