我正在尝试为换位密码制作解密功能

Question

我应该仅限于使用 len()、ord() 和 range() 函数。但是，我不知道我应该如何满足这些要求并最终做出了这个：

def swap(s: str, index0: int, index1: int):
    smaller = index0 if index0 < index1 else index1
    bigger = index0 if index0 >= index1 else index1
    if bigger >= len(s) or smaller < 0:
        return None
    ret = s[:smaller] + s[bigger] + s[smaller+1:]  # swap first
    ret = ret[:bigger] + s[smaller] + s[bigger+1:] # swap second
    return ret


def swap_encrypt(s: str, key:str):
    ret = s
    for key_chr in key:
        index = ascii_uppercase.index(key_chr)
        swap_this = index % len(ret)
        with_this = (swap_this - 1) % len(ret)
        ret = swap(ret, swap_this, with_this)

    return ret
s = ''
key = ''
def main2():
    s = input('Enter your message: ')
    s = cleanup(s)
    key = input('Enter your keyword: ')
    key = cleanup(key)
    ret= swap_encrypt((s), (key))
    print(cleanup(ret))

main2()

当我为消息输入 'Lsoth' 并为关键字输入 'a' 时，我得到 'HSOTL' 而不是 'SLOTH'

有没有办法既能满足我的要求，又能解决我的解密问题？

Answer 1

def swap_decrypt(msg: str, key: str):
ret = msg
for key_char in key:
    index = ord(key) + ord('A')
    swap_this = index % len(ret)
    with_this = (swap_this + 1) % len(ret)
    ret = swap2(ret, swap_this, with_this)
return ret

def main3():
    msg = input('Enter message for decrpytion: ')
    key = input('Enter keyword for decryption: ')
    msg = cleanup(msg)
    key = cleanup(key)
    ret = swap_decrypt(msg, key)
    print(cleanup(ret))

而不是 ascii_uppercase 做 index = ord(key) + ord('A')，并且 (swap_this -1) 应该是加而不是减 1。在这些小的更改之后，您的问题将得到解决。我还按顺序更改了一些变量，以便它更有意义。

我正在尝试为换位密码制作解密功能

I am trying to make a decryption function for transposition cipher

python

encryption