02-censo-de-letras.java

import java.util.Scanner;

public class J02 {

  public static void main(String[] args) {
    Scanner cin = new Scanner(System.in);
    int[] alfabeto = new int[26]; //En java, los valores son 0 por defecto.

    String s = cin.nextLine();

    for(int i=0; i<s.length(); i++) {
      char x = s.charAt(i);

      if('a' <= x && x <= 'z')
    alfabeto[x-'a']++;

      if('A' <= x && x <= 'Z')
    alfabeto[x-'A']++;
    }

    for(int i=0; i<26; i++)
      if(alfabeto[i] > 0)
    System.out.println((char)('a'+i) + ": " + alfabeto[i]);

  }

}