题解 | 小红的合数寻找

while True:
    try:
        num = int(input())
        zhishu_list = []
        heshu_list = []
        for i in range(num, 2*num+1):
            count = 0
            for j in range(1, i+1):
                if i % j == 0:
                    count += 1
            if count == 2:
                zhishu_list.append(i)
        # print(zhishu_list)
        for n in range(num, 2*num+1):
            if n > 1 and n not in zhishu_list:
                heshu_list.append(n)
        # print(heshu_list)
        if heshu_list:
            print(heshu_list[0])
        else:
            print(-1)

    except Exception as e:
        break