/*
* Now you have 3 attributes computed by you before: sn_, pk_, sk_
*
* Step-1
* Read each character C in data_ one by one, and encrypt them, then write to
* a new file. The output filename should be "letter".
* The encryption method is:
* C multiply itself sk_ times, then mod sn_
*
* Step-2
* Write pk_ to a file named "key.pub" in string, the format is: pk_[newline]sn_
* Write sk_ to a file named "key.prv" in string, the format is: sk_[newline]sn_
* NOTE: [newline] means a newline, don't output a string "[newline]" or you'll
* be mocked just like someone before.
*/
每个字符先X sk_
自乘sk_次，如何再 mod sn_ 取余数
pow();
mod();
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加密与解密：一个简单的C语言示例 阅读数 2万+
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