황소개발자

import sys input = sys.stdin.readline S = [] def do(order, num): global S if order == 'add': if num not in S: S.append(num) elif order == 'remove': if num in S: S.remove(num) elif order == 'check': if num in S: print(1) else: print(0) elif order == 'toggle': if num in S: S.remove(num) else: S.append(num) elif order == 'all': S = [i for i in range(1, 21)] elif order == 'empty': S = [] n = int(inp..