一个python自定义的加密解密函数

"""
皮蛋编程(https://www.pidancode.com)
创建日期：2022/4/24
功能描述：一个python自定义的加密解密函数
"""
def encrypt(key, s):
    b = bytearray(str(s).encode("gbk"))
    n = len(b)  # 求出 b 的字节数
    c = bytearray(n * 2)
    j = 0
    for i in range(0, n):
        b1 = b[i]
        b2 = b1 ^ key  # b1 = b2^ key
        c1 = b2 % 16
        c2 = b2 // 16  # b2 = c2*16 + c1
        c1 = c1 + 65
        c2 = c2 + 65  # c1,c2都是0~15之间的数,加上65就变成了A-P 的字符的编码
        c[j] = c1
        c[j + 1] = c2
        j = j + 2
    return c.decode("gbk")
def decrypt(key, s):
    c = bytearray(str(s).encode("gbk"))
    n = len(c)  # 计算 b 的字节数
    if n % 2 != 0:
        return ""
    n = n // 2
    b = bytearray(n)
    j = 0
    for i in range(0, n):
        c1 = c[j]
        c2 = c[j + 1]
        j = j + 2
        c1 = c1 - 65
        c2 = c2 - 65
        b2 = c2 * 16 + c1
        b1 = b2 ^ key
        b[i] = b1
    try:
        return b.decode("gbk")
    except:
        return "failed"
key = 15
s1 = encrypt(key, 'pidancode.com')
s2 = decrypt(key, s1)
print(s1, '\n', s2)

PHGGLGOGBGMGAGLGKGBCMGAGCG 
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