How to find the frequency of characters in a string in Haskell?

Question

How can I count the frequency of characters in a string and then output them in sort of a table?

For example, if I input the word \"happy\" the result would be

Answer 1

//Count the frequency of character in a string 

package waytocreateobject;
import java.util.Scanner;
public class Freqchara {

    public static void main(String[] args) {

        int c = 0, x = 0, loop = 26, space = 0;
        int count[] = new int[loop];
        //Arrays.fill(count, x);
        Scanner sc = new Scanner(System.in);
        String str =sc.nextLine();
        char[] charr = str.toCharArray();
        int aa = str.length();
        //System.out.println(str.charAt(10));
        //System.out.println(str.charAt(11));
        for (int mm = 0; mm < aa; mm++) {
            if (str.charAt(c) != '\0') {    //Considering characters from 'a' to 'z' only and ignoring others.
                if ((str.charAt(c) >= 'a') && (str.charAt(c) <= 'z')) {
                    x = (int) str.charAt(c) - (int) 'a';
                    // System.out.println(x);
                    count[x] = count[x] + 1;
                }
                c++;
            } else {}
        }

        // printing all the charcter
        int i = 97;
        for (int j = 0; j < loop; j++) {
            char ch = (char) (i + j);
            System.out.println(ch + "  occurs  " + count[j] + " times in the string");
        }
        System.out.println("  occurs " + space);
    }
}