IMPLEMENTATION OF RAIL FENCE

AIM:

            To write a  C++ program  to Implement Rail fence row & column transformation.

ALGORITHM:

Step 1:  Enter the plain text for encryption.

Step 2:  Enter the depth in integer (number of rows)

Step 3: In the rail fence cipher, the plaintext is written downwards and diagonally on successive "rails" of an imaginary fence, then moving up when we reach the bottom rail.

Step 4: When we reach the top rail, the message is written downwards again until the whole plaintext is written out.

Step 5: The message is then read off in rows. Thus, the cipher text is generated.

PROGRAM:

#include<iostream>

using namespace std;

int main()

{

inti,j=0,d,k=0;

char p[50],ct[50][50];

cout<<"Enter the plain text:\n";

cin>>p;

cout<<"\nEnter the depth in the integer:";

cin>>d;

            //declare null for empty array values

for(i=0;i<50;i++)

            {

for(j=0;j<50;j++)

                       {

ct[i][j]='\0';

                        }

            }

            k=0;

       //loop up to string lenght of the plaintext

            {

for(i=0;i<strlen(p);i++)

            {

for(j=0;j<d;j++)

                        {

                                    if(k<=strlen(p))

ct[i][j]=p[k];

                                    k++;

                        }

ct[i][j]='\0';

                        }

            }

for(i=0;i<d;i++)

            {

            for(j=0;j<strlen(p);j++)

                        {

if(ct[j][i]!='\0')

                                       {

printf("%c",ct[j][i]);

                                       }

                        }

cout<<"\n";

            }

            // Read the text

cout<<"\nThe encrypted text is:\n";

for(i=0;i<d;i++)

            {

for(j=0;j<strlen(p);j++)

                        {

if(ct[j][i]!='\0')

cout<<ct[j][i];

                      }

            }

            return 0;

}

OUTPUT: