#include <stdio.h>
#include <unordered_map>
using namespace std;
int n,tip,x,i;
unordered_map <int,bool> uhash;
int main() {
freopen("hashuri.in","r",stdin);
freopen("hashuri.out","w",stdout);
scanf("%d",&n);
for (i=1;i<=n;i++) {
    scanf("%d %d",&tip,&x);
    if (tip==1) uhash[x]=true; else
    if (tip==2) uhash.erase(x); else
    if (tip==3) {
        if (uhash.find(x)==uhash.end()) puts("0"); else
            puts("1");
    }
}
return 0;
}