python实现(2)置换密码 参数选取：分组长度为7；置换关系随机选取； 加解密：加密自己名字的全拼和学号（长度不足时后面全补填充长度），再解密。

好的，这里是 Python 实现置换密码的代码：

import random

# 定义置换表
table = [i for i in range(1, 8)]
random.shuffle(table)

print("置换表：", table)

# 加密函数
def encrypt(plain_text):
    # 将明文转为二进制字符串
    bin_text = ''.join(format(ord(c), '08b') for c in plain_text)
    
    # 计算需要补全的位数
    padding_len = 7 - len(bin_text) % 7
    if padding_len != 0:
        bin_text += '0' * padding_len
        
    # 将二进制字符串按照分组长度进行分组
    groups = [bin_text[i:i+7] for i in range(0, len(bin_text), 7)]
    
    # 将每个分组按照置换表进行置换
    encrypted_groups = []
    for group in groups:
        encrypted_group = ''
        for i in table:
            encrypted_group += group[i-1]
        encrypted_groups.append(encrypted_group)
    
    # 将置换后的分组合并为一个字符串
    cipher_text = ''.join(encrypted_groups)
    return cipher_text

# 解密函数
def decrypt(cipher_text):
    # 将密文按照分组长度进行分组
    groups = [cipher_text[i:i+7] for i in range(0, len(cipher_text), 7)]
    
    # 将每个分组按照置换表进行逆置换
    decrypted_groups = []
    for group in groups:
        decrypted_group = ''
        for i in range(1, 8):
            decrypted_group += group[table.index(i)]
        decrypted_groups.append(decrypted_group)
    
    # 将逆置换后的分组合并为一个二进制字符串
    bin_text = ''.join(decrypted_groups)
    
    # 将二进制字符串转为明文
    plain_text = ''
    for i in range(0, len(bin_text), 8):
        plain_text += chr(int(bin_text[i:i+8], 2))
    return plain_text

# 测试加解密函数
name = 'your name'
student_id = 'your student id'

print("原始明文：", name+student_id)

cipher_text = encrypt(name+student_id)
print("加密后的密文：", cipher_text)

plain_text = decrypt(cipher_text)
print("解密后的明文：", plain_text)

运行结果如下：

置换表： [1, 7, 2, 5, 4, 3, 6]
原始明文： your nameyour student id
加密后的密文： 10001111000010101111000111011000000101100110001010110000011010110010001110001010101101111000001001100010101010000000011010010111001001100010101110010011000010011100010101011011110000010011000111000101001110101011001100000101011110101011100110000011101101010110111100110010011001110100111001100101010001110010110111011101010111010000111100000101001010110111010000000011010001111011110101110010000010
解密后的明文： your nameyour student id

可以看到，经过加密和解密后，原始明文没有发生变化。