import java.util.Scanner;

public class EncryptAndDecrypt
{
    private static String all = "!abcdefghijklmnopqrstuvwxyz";

    public static String enryptLine (String s, int shift)
    {
        char[] input = s.toCharArray();

        for (int i = 0; i <input.length; i++)
        {
            if (input[i] != ' ')
            {
                int loc = shift + all.indexOf(input[i]);

                if (loc > 26)
                {
                    loc = (loc - 26);
                }
                input[i] = all.charAt(loc);

            }
        }
        String answer = String.valueOf (input);   
        return answer;
    }

    public static String decryptLine (String s, int shift) 
    { 
        char[] input = s.toCharArray(); 
        for (int i = 0; i <input.length; i++) 
        { 
            if (input[i] != ' ') 
            { 
                int loc = all.indexOf(input[i]) - shift; 

                if (loc <= 0) 
                { 
                    loc = 26 + loc; 
                } 
                input[i] = all.charAt(loc); 
            } 
        } 
        String answer = String.valueOf (input); 
        return answer; 
    } 

    public static void main (String args [])
    {
        System.out.println ("Encryption and Decryption");
        Scanner sr = new Scanner (System.in);

        System.out.println("Input the sentence to be decoded - Only alphabets and spaces and lower case");
        String Line = sr.nextLine();

        System.out.println("Input shift value - 1, 2.....26");
        int value = sr.nextInt();

        String answer = enryptLine (Line, value);
        System.out.println ("Encrypted Text = " + answer);    

        answer = decryptLine (answer, value);
        System.out.println ("Encrypted Text = " + answer); 
    }
}