字符串加密与解密，输入一字符串，按如下规则加密，将原文中每个字符转换为对应的ascii码后，再将该ascii码加上一100至200之间的整数得到的数值即为该字符对应的密文；解密即为上述过程的逆运算。将该字符串加密后再解密，并且显示原文、密文、解密后文本，代码用python怎么实现

加密代码如下：

import random

def encrypt(string):
    encrypted = ''
    for char in string:
        ascii_code = ord(char)
        random_number = random.randint(100, 200)
        encrypted_ascii = ascii_code + random_number
        encrypted += chr(encrypted_ascii)
    return encrypted

解密代码如下：

def decrypt(string):
    decrypted = ''
    for char in string:
        encrypted_ascii = ord(char)
        random_number = random.randint(100, 200)
        ascii_code = encrypted_ascii - random_number
        decrypted += chr(ascii_code)
    return decrypted

加密和解密的过程都是通过遍历字符串中的每个字符，先将其转换为ascii码，然后加上一个随机数得到密文（加密），或者减去同样的随机数得到明文（解密）。注意，加密和解密时的随机数必须相同，否则解密失败。

完整的代码如下：

import random

def encrypt(string):
    encrypted = ''
    for char in string:
        ascii_code = ord(char)
        random_number = random.randint(100, 200)
        encrypted_ascii = ascii_code + random_number
        encrypted += chr(encrypted_ascii)
    return encrypted

def decrypt(string):
    decrypted = ''
    for char in string:
        encrypted_ascii = ord(char)
        random_number = random.randint(100, 200)
        ascii_code = encrypted_ascii - random_number
        decrypted += chr(ascii_code)
    return decrypted

string = input("请输入字符串：")
encrypted_string = encrypt(string)
decrypted_string = decrypt(encrypted_string)

print("原文：", string)
print("密文：", encrypted_string)
print("解密后文本：", decrypted_string)