Hill Cipher in C Added

C/Cryptography/Hill_Cipher.c

@@ -0,0 +1,38 @@
+#include<stdio.h>
+#include<string.h>
+int main() {
+    unsigned int a[3][3] = { { 6, 24, 1 }, { 13, 16, 10 }, { 20, 17, 15 } };
+    unsigned int b[3][3] = { { 8, 5, 10 }, { 21, 8, 21 }, { 21, 12, 8 } };
+    int i, j;
+    unsigned int c[20], d[20];
+    char msg[20];
+    int determinant = 0, t = 0;
+    ;
+    printf("Enter plain text\n ");
+    scanf("%s", msg);
+    for (i = 0; i < 3; i++) {
+        c[i] = msg[i] - 65;
+        printf("%d ", c[i]);
+    }
+    for (i = 0; i < 3; i++) {
+        t = 0;
+        for (j = 0; j < 3; j++) {
+            t = t + (a[i][j] * c[j]);
+        }
+        d[i] = t % 26;
+    }
+    printf("\nEncrypted Cipher Text :");
+    for (i = 0; i < 3; i++)
+        printf(" %c", d[i] + 65);
+    for (i = 0; i < 3; i++) {
+        t = 0;
+        for (j = 0; j < 3; j++) {
+            t = t + (b[i][j] * d[j]);
+        }
+        c[i] = t % 26;
+    }
+    printf("\nDecrypted Cipher Text :");
+    for (i = 0; i < 3; i++)
+        printf(" %c", c[i] + 65);
+    return 0;
+}

README.md

@@ -101,7 +101,7 @@
 | 3.  | Columnar Transposition Cipher | [C](https://github.com/Kumar-laxmi/Algorithms/blob/main/C/Cryptography/ColumnarTranspositionCipher.c), [C++](https://github.com/Kumar-laxmi/Algorithms/blob/main/C%2B%2B/Cryptography/ColumnarTranspositionCipher.cpp), [Java](https://github.com/Kumar-laxmi/Algorithms/blob/main/Java/Cryptography/ColumnarTranspositionCipher.java), [Python](https://github.com/Kumar-laxmi/Algorithms/blob/main/Python/Cryptography/ColumnarTranspositionCipher.py) |
 | 4.  | Diffie - Hellman Algorithm | [Python](https://github.com/Kumar-laxmi/Algorithms/blob/main/Python/Cryptography/DiffieHellman.py) |
 | 5.  | Elgamal Cryptosystem | [C](https://github.com/Kumar-laxmi/Algorithms/blob/main/C/Cryptography/Elgamal.c), [C++](https://github.com/Kumar-laxmi/Algorithms/blob/main/C%2B%2B/Cryptography/Elgamal.cpp), [Java](https://github.com/Kumar-laxmi/Algorithms/blob/main/Java/Cryptography/Elgamal.java), [Python](https://github.com/Kumar-laxmi/Algorithms/blob/main/Python/Cryptography/Elgamal.py) | 
-| 6.  | Hill Cipher | [C++](https://github.com/Kumar-laxmi/Algorithms/blob/main/C%2B%2B/Cryptography/HillCipher.cpp), [Java](https://github.com/Kumar-laxmi/Algorithms/blob/main/Java/Cryptography/HillCipher.java), [Python](https://github.com/Kumar-laxmi/Algorithms/blob/main/Python/Cryptography/HillCipher.py) |
+| 6.  | Hill Cipher | [C](https://github.com/Kumar-laxmi/Algorithms/blob/main/C/Cryptography/Hill_Cipher.c), [C++](https://github.com/Kumar-laxmi/Algorithms/blob/main/C%2B%2B/Cryptography/HillCipher.cpp), [Java](https://github.com/Kumar-laxmi/Algorithms/blob/main/Java/Cryptography/HillCipher.java), [Python](https://github.com/Kumar-laxmi/Algorithms/blob/main/Python/Cryptography/HillCipher.py) |
 | 7.  | Homophonic Substitution | [C](https://github.com/Kumar-laxmi/Algorithms/blob/main/C/Cryptography/homophonic_substitution.c), [C++](https://github.com/Kumar-laxmi/Algorithms/blob/main/C%2B%2B/Cryptography/homophonic_substitution.cpp), [Java](https://github.com/Kumar-laxmi/Algorithms/blob/main/Java/Cryptography/HomophonicSubstitution.java), [Python](https://github.com/Kumar-laxmi/Algorithms/blob/main/Python/Cryptography/homophonic_Substitution.py) | 
 | 8.  | Morse Code | [C](https://github.com/Kumar-laxmi/Algorithms/blob/main/C/Cryptography/MorseCodeConvortor.c), [C++](https://github.com/Kumar-laxmi/Algorithms/blob/main/C%2B%2B/Cryptography/MorseCodeConvotor.cpp), [Java](https://github.com/Kumar-laxmi/Algorithms/blob/main/Java/Cryptography/MorseCodeConverter.java), [Python](https://github.com/Kumar-laxmi/Algorithms/blob/main/Python/Cryptography/MorseCodeConvortor.py) |
 | 9.  | Playfair Cipher | [C](https://github.com/Kumar-laxmi/Algorithms/blob/main/C/Cryptography/playfair_cipher.c), [C++](https://github.com/Kumar-laxmi/Algorithms/blob/main/C%2B%2B/Cryptography/playfair_cipher.cpp), [Java](https://github.com/Kumar-laxmi/Algorithms/blob/main/Java/Cryptography/PlayfairCipher.java), [Python](https://github.com/Kumar-laxmi/Algorithms/blob/main/Python/Cryptography/playfair_cipher.py) |