image.png

    1. #include<bits/stdc++.h>
    2. using namespace std;
    4. string encrypt(string pt, string key)
    5. {
    6.     string ct = "";    // 密文
    7.     int k = 0;         //控制key的长度
    8.            //ceil(a)   返回大于a的最小整数
    9.     int row = ceil((float)pt.length() / key.length());   // 行数   
    10.     int col = key.length();                             //列数
    12.     std::vector<std::vector<int> > Matx(row, vector<int>(col, 0));     ///初始化row * col二维动态数组Matx，初始化值为0
    14.     cout << "\n加密矩阵为 :" << endl;
    15.     for (int i = 0; i < row; i++)
    16.     {
    17.         for (int j = 0; j < col; j++)
    18.         {
    19.             if (k < pt.length())
    20.             {
    21.                 cout <<(char) (Matx[i][j] = pt[k++]) << "  ";
    22.             }
    23.             else
    24.             {
    25.                 cout << (char)(Matx[i][j] = 'x') << "  ";
    26.             }
    27.         }
    28.         cout << endl;
    29.     }
    30.     for (int i = 0; i < col; i++)
    31.     {
    32.         for (int j = 0; j < row; j++)
    33.         {
    34.             ct += Matx[j][key.find(i + '1')]; //密文抄送
    35.         }
    36.     }
    38.     return ct;
    39. }
    41. string decrypt(string ct, string key)
    42. {
    43.     string pt = ""; // plaintext
    44.     int k = 0; // ciptext iterator
    46.     int num_row = ceil((float)ct.length() / key.length());
    47.     int num_col = key.length();
    48.     std::vector<std::vector<int> > Matx(num_row, vector<int>(num_col, 0));
    50.     for (int i = 0; i < num_col; i++)
    51.     {
    52.         for (int j = 0; j < num_row; j++)
    53.         {
    54.             Matx[j][key.find(i + '1')] = ct[k++];
    55.         }
    56.     }
    58.     for (int i = 0; i < num_row; i++)
    59.     {
    60.         for (int j = 0; j < num_col; j++)
    61.         {
    62.             pt += Matx[i][j];
    63.         }
    64.     }
    65.     return pt;
    66. }
    68. int main()
    69. {
    70.     string plaintext, key, ciphertext, decryptext;
    72.     /*cout << "Enter text : ";
    73.     cin >> plaintext;*/
    74.     plaintext = "transpoipher";
    76.     /*cout << "Enter key  : ";
    77.     cin >> key;*/
    78.     key = "4231";
    80.     cout << "\n明文 \t:" << plaintext << endl;
    81.     ciphertext = encrypt(plaintext, key);
    82.     cout << "\n密文 \t: " << ciphertext << endl;
    84.     decryptext = decrypt(ciphertext, key);
    85.     cout << "\n解密 \t: " << decryptext << endl;
    86. }