LetterIndex

import java.util.HashMap;
import java.util.Scanner;

public class LetterIndex {
    public static void main(String[] args) {
        Scanner scan = new Scanner(System.in);

        char[] arr = "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".toCharArray();
        System.out.println("Input text: ");
        String text = scan.nextLine();
        HashMap<Character, Integer> map = new HashMap();

        for (int i = 0; i < arr.length; i++) {
            map.put(arr[i], i);
        }

        for (int i = 0; i < text.length(); i++) {
            System.out.println(text.charAt(i) + " -> " + map.get(text.charAt(i)));
        }
    }
}