#include <iostream>
#include <cstdio>
#include <set>

#define fs fscanf
#define fp fprintf

using namespace std;
typedef set<int>::iterator iter;


FILE *f, *g;

int n, i, x, y;
set <int> s;

void operation1(int y)
{
    s.insert(y);
}

void operation2(int y)
{
    iter it = s.find(y);
    if(it != s.end())
        s.erase(it);
}

void operation3(int y)
{
    iter it = s.find(y);
    if(it == s.end())
        fp(g, "0\n");
    else
        fp(g, "1\n");
}

int main()
{
    f = fopen("hashuri.in", "r");
    g = fopen("hashuri.out", "w");
    //set stl
    fs(f, "%d", &n);
    for(i = 1; i <= n; i ++)
    {
        fs(f, "%d%d", &x, &y);
        if(x == 1)
            operation1(y);
        else
        if(x == 2)
            operation2(y);
        else
        if(x == 3)
            operation3(y);
    }

    fclose(f);
    fclose(g);
    return 0;
}