def main():
    with open('hashuri.in', 'r') as f:
        lines = f.readlines()

    N = int(lines[0].strip())
    operations = [line.strip().split() for line in lines[1:]]

    result = []
    multime = set()

    for op, x in operations:
        x = int(x)
        if op == '1':
            multime.add(x)
        elif op == '2':
            multime.discard(x)
        elif op == '3':
            result.append('1' if x in multime else '0')

    with open('hashuri.out', 'w') as f:
        f.write('\n'.join(result) + '\n')

main()