I'm having trouble trying to get the character at an index

Question

This is my code:

package ch3;

import java.util.Scanner;

public class caesarCypher {

    static String inp;

    public static void main(String[] args) {
        int input;
        int x = 0;
        Scanner scan = new Scanner(System.in);
        inp = scan.nextLine();

        input = inp.length();
        System.out.println(input + inp);
        while (x < input) {
            x += 1;
            inp =  ((inp.charAt(x)) - 12);
        }   
    }
}

how would I go about setting the index of inp to x? So to rephrase, I'm trying to subtract the character, for example, a - 12 on the ASCII table.

Answer 1

Try using a char array:

public class caesarCypher {

    static String inp;

    public static void main(String[] args) {
        int input;
        Scanner scan = new Scanner(System.in);
        inp = scan.nextLine();
        char[] inpArr = inp.toCharArray();

        input = inp.length();
        System.out.println(input + inp);
        for( int i = 0; i < input; i++)
        {
            inpArr[i] -= 12;
        }

        inp = new String( inpArr);
    }
}

As a side note, you will get an IndexOutOfBoundsException from the below code. Use x, then increment it.

while (x < input) {
    x += 1;
    inp =  ((inp.charAt(x)) - 12);
}