某加密算法的加密部分Python程序段如下：

def encrypt(msg,key):

result = ""

size = len(msg)

for i in range(0,size):

    result = result + msg[(i - key) % size]

return result

msg = input("请输入明文：")

key = int(input("请输入密钥："))

re =             

print(re)