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Ceaser cipher

import java.util.*;


class Caesar {

    public static void main(String[] a) {

        Scanner sc = new Scanner(System.in);

        System.out.print("Text: ");

        String t = sc.nextLine();

        System.out.print("Shift: ");

        int s = sc.nextInt();


        String c = "";

        for (char ch : t.toCharArray())

            c += Character.isLetter(ch) ?

                 (char)((ch - (Character.isUpperCase(ch)?'A':'a') + s) % 26 

                 + (Character.isUpperCase(ch)?'A':'a')) : ch;


        System.out.println("Cipher: " + c);


        String d = "";

        for (char ch : c.toCharArray())

            d += Character.isLetter(ch) ?

                 (char)((ch - (Character.isUpperCase(ch)?'A':'a') - s + 26) % 26 

                 + (Character.isUpperCase(ch)?'A':'a')) : ch;


        System.out.println("Decrypted: " + d);

    }

}




Verman cipher

import java.util.*;

class Vernam {
    public static void main(String[] a) {
        Scanner sc = new Scanner(System.in);
        System.out.print("Text: ");
        String p = sc.nextLine();
        System.out.print("Key: ");
        String k = sc.nextLine();

        String c = "";
        for (int i = 0; i < p.length(); i++)
            c += (char)(p.charAt(i) ^ k.charAt(i));
        System.out.println("Cipher: " + c);

        String d = "";
        for (int i = 0; i < c.length(); i++)
            d += (char)(c.charAt(i) ^ k.charAt(i));
        System.out.println("Decrypted: " + d);
    }
}




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