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Vigenère cipher

After a long time, I've been doing some coding, well I was teaching.I had to do Vigenère cipher in Java.

First of all, What is "Vigenère cipher"?
The Vigenère cipher is a method of encrypting alphabetic text by using a series of interwoven Caesar ciphers based on the letters of a keyword. It is a form of polyalphabetic substitution (Wikipedia) 

There are a lot of methods for creating this Encryption method. For those who know how to code with OOP Principles, this code may look like Babies Rusk. 😋

We can code this in two ways.
Method 1
We use the Vigenère Matrix to find the Cipher Text. We will create the Matrix through looping and row will be either plaintext and column will be key string.

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import java.util.*;
public class Vigenere
{
 public static void main(String [] args)
 {
  Scanner scan = new Scanner (System.in);
  System.out.print("Enter the message= ");
  String plain = scan.nextLine();
  plain=plain.toUpperCase();
  System.out.print("Enter the key= ");
  String key = scan.nextLine();
  key=key.toUpperCase();
  char [][] vignerematrix = new char [26][26];
  char [] alp = {'A','B','C','D','E','F','G','H','I','J','K','L','M','N','O','P','Q','R','S','T','U','V','W','X','Y','Z'};
  int num = 0;
  int t = 0;
  for(int i=0;i<=25;i++)
  {
   for (int j=0;j<=25;j++)
   {
    num = (i+j)%26;
    vignerematrix [i][j] = alp[num]; 
   }
  }
  int strlen = plain.length();
  int keylen = key.length();
  char onstr = 'a';
  char onkeyey = 'a';
  for(int i=0;i<strlen;i++)
  {
   onstr = plain.charAt(i);
   onkeyey = key.charAt(i%keylen);
   int row=0;
   int col=0;
   
   for(int j=0;j<26;j++)
   {
    if(onstr == alp[j])
    {
     row = j;
     break;
    }
   }
   
   for(int j=0;j<26;j++)
   {
    if(onkeyey == alp[j])
    {
     col = j;
     break;
    }
   }
   System.out.print(vignerematrix[row][col]);
  }
 } 
}




Method 2
Calculate the Cipher key with adding the Plain text characters and key characters in order and finding the Cipher text through.

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import java.util.*;
public class VigenereSimplified
{
 public static void main(String [] args)
 {
  Scanner scan = new Scanner (System.in);
  System.out.print("Enter the message= ");
  String plain = scan.nextLine();
  plain=plain.toUpperCase();
  System.out.print("Enter the key= ");
  String key = scan.nextLine();
  key=key.toUpperCase();
  char [] alp = {'A','B','C','D','E','F','G','H','I','J','K','L','M','N','O','P','Q','R','S','T','U','V','W','X','Y','Z'};
  String cipherText="";
  int cipher=0;
  
  for(int i=0;i<plain.length();i++)
  {
   cipher = 0;
   for(int j=0;j<26;j++)
   {
    if(plain.charAt(i) == alp[j])
    {
     cipher += j;
    }
    if(key.charAt(i%key.length()) == alp[j])
    {
     cipher += j;
    }
   }
   cipherText += alp[cipher%26];
  }
  
  System.out.println(plain+" + "+key+" = "+cipherText);
 } 
}


These are some basic coding styles, which is hard coding.

Hey! There may be more than one solution for one problem.
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