- //
- // main.cpp
- // RSA
- //
- // Created by liujan on 10/21/14.
- // Copyright (c) 2014 liujan. All rights reserved.
- //
- #include <iostream>
- #include "cmath"
- using namespace std;
- long long p = 1949, q = 3413;
- long long N = p * q;
- long long e = 13007, d = 511;
- //对a的b次幂取模 m(大数取模)
- long long Mod(long long a, long long b, long long m){
- long long r = 1;
- for (long long j = 0; j < b; j++){
- r = (r * a) % m;
- }
- return r;
- }
- //对输入信息进行rsa编码
- long long * rsaEncode(string message){
- size_t length = message.length();
- long long *ascii = new long long[length]; //存储信息的每个字符
- long long *code = new long long[length]; //存储每个字符的rsa编码
- for (size_t i = 0; i < length; i++){
- ascii[i] = message[i];
- }
- for (size_t i = 0; i < length; i++){
- code[i] = Mod(ascii[i], e, N ); //C=M^e (modN)
- }
- return code;
- }
- //根据rsa编码得到原来的信息
- string rsaDecode(long long code[], size_t n){
- long long *ascii = new long long[n];
- string message = "";
- for (size_t i = 0; i < n; i++){
- ascii[i] = Mod(code[i], d, N); //M=C^d (modN)
- message += ((char)(ascii[i]));
- }
- return message;
- }
- int main(int argc, const char * argv[]) {
- string message = "Hello World!";
- size_t length = message.length();
- long long *a = rsaEncode(message);
- string newmessage = rsaDecode(a, length);
- cout << newmessage << endl;
- return 0;
- }
来源: http://www.phpxs.com/code/1004153/