维吉尼亚密码原理详解与算法实现工程文件

#include <iostream> #include <string> #include <string.h> #pragma warning(disable:4996) /* * @Author:timerring * @Date: 2021-10-20 14:05:49 * @LastEditTime: 2021-10-22 08:11:15 * @FilePath:c:\Users\timerring\Vigenere.cpp */ using namespace std; const int N = 26; //定义二维密码表 char v[N][N] = { {'A','B','C','D','E','F','G','H','I','J','K','L','M','N','O','P','Q','R','S','T','U','V','W','X','Y','Z'} }; int number(char x) {//把行号字母对应到数字空间上 char y = 'a'; for (int i = 0; i < N; i++) { if (x == (y + i)) return i; } } void encryption(string msg, string key) {//定义加密过程 cout << "plaintext:"; cin >> msg; cout << "key:"; cin >> key; int mlen, klen; //获取明文和密钥的长度 mlen = msg.length(); klen = key.length(); char* p, * q, * t;//明文，初始密钥，密钥串 //把string换成char p = new char[msg.length() + 1]; //用strcpy函数进行对应的复制 strcpy(p, msg.c_str()); q = new char[key.length() + 1]; strcpy(q, key.c_str()); t = new char[msg.length() + 1]; int j = 0; for (int i = 0; i < mlen; i++) { t[i] = q[j]; j++; j = j % klen; } cout << "ciphertext:"; for (int i = 0; i < mlen; i++) //按位输出密文字符 cout << v[number(t[i])][number(p[i])]; cout << endl; } void decryption(string c, string key) {//定义解密过程 cout << "ciphertext:"; cin >> c; cout << "key:"; cin >> key; int clen, klen; clen = c.length(); klen = key.length(); char* p, * q, * t;//密文，初始密钥，密钥串 //将string换成char p = new char[c.length() + 1]; //用strcpy函数进行对应的复制 strcpy(p, c.c_str()); q = new char[key.length() + 1]; strcpy(q, key.c_str()); t = new char[c.length() + 1]; int j = 0; for (int i = 0; i < clen; i++) { t[i] = q[j]; j++; j = j % klen; }//生成密钥 cout << "plaintext:"; for (int i = 0; i < clen; i++) for (int j = 0; j < N; j++) if (v[number(t[i])][j] == p[i]) { cout << char(j + 97); break; } cout << endl; } int main() { for (int i = 1; i < N; i++) { for (int j = 0; j < N; j++) { v[i][j] = v[i - 1][(j + 1) % N]; }//将方阵进行初始化 } cout << "You are welcome to use Vigenere in SDU\n" << endl; cout << "Please enter the corresponding operation number:" << endl; int flag; do { cout << "1.Encrypt\n2.Decrypt\n"; cin >> flag; string m, key; if (flag == 1)encryption(m, key); else if (flag == 2) decryption(m, key); else break; } while (flag != 3); return 0; }