#include <unordered_set>
#include <bits/stdc++.h>

using namespace std;

int N;
unordered_set<int> A;

const int kBuffSize = 655536;

#define fastcall __attribute__((optimize("-O3")))
#define inline __inline__ __attribute__((always_inline))


inline fastcall char getChar()
{
    static char buff[kBuffSize];
    static int pos = kBuffSize;
    if (pos == kBuffSize)
    {
        fread(buff, 1, kBuffSize, stdin);
        pos = 0;
    }
    return buff[pos++];
}

inline fastcall int readInt()
{
    int q = 0;
    char c;
    do
    {
        c = getChar();
    }
    while (!isdigit(c));
    do
    {
        q = (q << 1) + (q << 3) + (c - '0');
        c = getChar();
    }
    while (isdigit(c));
    return q;
}

char outBuff[kBuffSize];
int outPtr;

inline fastcall void putChar(const char &C)
{
    outBuff[outPtr++] = C;
    if (outPtr == kBuffSize)
    {
        fwrite(outBuff, 1, kBuffSize, stdout);
        outPtr = 0;
    }
}

inline fastcall void writeInt(int X)
{
    char digs[10];
    int n = 0, q;
    do
    {
        q = X / 10;
        digs[n++] = X - (q << 1) - (q << 3) + '0';
        X = q;
    }
    while (X);
    while (n--)
    {
        putChar(digs[n]);
    }
    putChar('\n');
}

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

    int op, x;

    A.reserve(1 << 21);
    for (N = readInt(); N; --N)
    {
        op = readInt();
        x = readInt();

        if (op == 1)
        {
            A.insert(x);
            continue;
        }
        if (op == 2)
        {
            A.erase(x);
            continue;
        }
        writeInt((A.find(x) != A.end()));
    }
    fclose(stdin);
    fwrite(outBuff, 1, outPtr, stdout);
    fclose(stdout);
    return 0;
}