python - 使用python解扰单词

Question

以下代码使用步长随机加扰文本，我想编写一个函数来解扰并获取原始字符串如何做。

def scramble(plain):
    cipher = ""
    step = 7
    for x in range(0, step):
        for y in range(x, len(plain), step):
            cipher += plain[y]
    return cipher

Answer 1

只需反转模式：

def unscramble(cipher):
    plain = [""] * len(cipher)
    step = 7
    i = 0
    for x in range(0, step):
        for y in range(x, len(plain), step):
            plain[y] = cipher[i]
            i += 1
    return ''.join(plain)