Hill.cpp

#include <iostream>
using namespace std;
void getKeyMatrix(string key, int keyMatrix[][3]){
	int k = 0;
	for (int i = 0; i < 3; i++){
		for (int j = 0; j < 3; j++){
			keyMatrix[i][j] = (key[k]) % 65;
			k++;
		}
	}
}
void encrypt(int cipherMatrix[][1],int keyMatrix[][3],int messageVector[][1]){
	int x, i, j;
	for (i = 0; i < 3; i++){
		for (j = 0; j < 1; j++){
			cipherMatrix[i][j] = 0;
			for (x = 0; x < 3; x++){
				cipherMatrix[i][j] +=
					keyMatrix[i][x] * messageVector[x][j];
			}
			cipherMatrix[i][j] = cipherMatrix[i][j] % 26;
		}
	}
}
void HillCipher(string message, string key){
	int keyMatrix[3][3];
	getKeyMatrix(key, keyMatrix);
	int messageVector[3][1];
	for (int i = 0; i < 3; i++) messageVector[i][0] = (message[i]) % 65;
	int cipherMatrix[3][1];
	encrypt(cipherMatrix, keyMatrix, messageVector);
	string CipherText;
	for (int i = 0; i < 3; i++) CipherText += cipherMatrix[i][0] + 65;
	cout << " Ciphertext:" << CipherText;
}
int main()
{
	string message = "ACT";
	string key = "GYBNQKURP";
	HillCipher(message, key);
	return 0;
}