C code to Encrypt & Decrypt Message using Vernam Cipher

Check out new C program to implement Vernam Cipher to encrypt and decrypt a given message on Turbo C software. Code is given below:

#include<stdio.h>

char arr[26][26];
char message[22],key[22],emessage[22],retMessage[22];
int findRow(char);
int findColumn(char);
int findDecRow(char,int);

int main()
{
 int i=0,j,k,r,c;
 clrscr();
 k=96;

 for(i=0;i<26;i++)
 {
   k++;
   for(j=0;j<26;j++)
   {
    arr[i][j]=k++;
    if(k==123)
    k=97;
   }
 }

 printf("\nEnter message\n");
 gets(message);
 printf("\nEnter the key\n");
 gets(key);
 // Encryption

 for(i=0;key[i]!=NULL;i++)
 {
   c=findRow(key[i]);
   r=findColumn(message[i]);
   emessage[i]=arr[r][c];
 }
 emessage[i]='\0';

 printf("\n Encrypted message is:\n\n");

 for(i=0;emessage[i]!=NULL;i++)
 printf("%c",emessage[i]);

 //decryption

 for(i=0;key[i]!=NULL;i++)
 {
    c=findColumn(key[i]);
    r=findDecRow(emessage[i],c);
    retMessage[i]=arr[r][0];
  }
  retMessage[i]='\0';
  printf("\n\nMessage Retrieved is:\n\n");
  for(i=0;retMessage[i]!=NULL;i++)
  printf("%c",retMessage[i]);
 getch();
 return(0);
}
int findRow(char c)
{
  int i;
  for(i=0;i<26;i++)
  {
   if(arr[0][i]==c)
   return(i);
  }
}

int findColumn(char c)
{
  int i;
  for(i=0;i<26;i++)
  {
   if(arr[i][0]==c)
   return(i);
  }
}

int findDecRow(char c,int j)
{
  int i;
  for(i=0;i<26;i++)
  {
   if(arr[i][j]==c)
   return(i);
  }
}

//Output Of the above program:-

Result of Vernam Cipher

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