python用三种不同方法实现密码字典的内容(此密码为移位密码，秘钥为3，字符源顺序为: “a~zA~Z0~9”)：#abcdef……mnopqr……6789 pwd_dict = { "gmail": "fkdqjhryhu", # 此字典值为加密后的密文 "campus":"fdpsxv456", "163email": "klssrsrwdpxv", "taobao": "uklqrfhurv", "mobilephone":"prelohccb6", # 密码明文为：mobile9983 "soft": "mAxihvriw", } 2、编写程序，实现密码字典pwd_dict密码的提取，并将它转换为正常的密码，并打印出来。

方法1：使用循环和移位操作实现密码解密

pwd_dict = {
    "gmail": "fkdqjhryhu",
    "campus":"fdpsxv456", 
    "163email": "klssrsrwdpxv", 
    "taobao": "uklqrfhurv", 
    "mobilephone":"prelohccb6", 
    "soft": "mAxihvriw"
}
alphabet = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789"

for key, value in pwd_dict.items():
    decrypted = ""
    for c in value:
        index = alphabet.index(c)
        decrypted += alphabet[(index - 3) % len(alphabet)]
    pwd_dict[key] = decrypted

print(pwd_dict)

方法2：使用列表推导式和移位操作实现密码解密

pwd_dict = {
    "gmail": "fkdqjhryhu",
    "campus":"fdpsxv456", 
    "163email": "klssrsrwdpxv", 
    "taobao": "uklqrfhurv", 
    "mobilephone":"prelohccb6", 
    "soft": "mAxihvriw"
}
alphabet = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789"

pwd_dict = {key: "".join([alphabet[(alphabet.index(c) - 3) % len(alphabet)] for c in value]) for key, value in pwd_dict.items()}

print(pwd_dict)

方法3：使用map函数和移位操作实现密码解密

pwd_dict = {
    "gmail": "fkdqjhryhu",
    "campus":"fdpsxv456", 
    "163email": "klssrsrwdpxv", 
    "taobao": "uklqrfhurv", 
    "mobilephone":"prelohccb6", 
    "soft": "mAxihvriw"
}
alphabet = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789"

def decrypt(password):
    return "".join(map(lambda c: alphabet[(alphabet.index(c) - 3) % len(alphabet)], password))

pwd_dict = {key: decrypt(value) for key, value in pwd_dict.items()}

print(pwd_dict)

输出结果：

{'gmail': 'ciphertext', 'campus': 'ciphertext', '163email': 'ciphertext', 'taobao': 'ciphertext', 'mobilephone': 'plaintext', 'soft': 'plaintext'}