import java.util.*;
import java.lang.Character;

class Counter { 
  int i = 1; 
}

public class Statistics {
  public static void main(String[] args) {
    HashMap hm = new HashMap();
    for(int i = 0; i < 26; i++) {
        Character r = new Character((char)(Math.random()*26 + 'a'));
        if(hm.containsKey(r))
           ((Counter)hm.get(r)).i++;
        else
           hm.put(r, new Counter());
    }
    for(int i = 0; i < 26; i++) {
      Character r = new Character((char)(i+'a'));
      if(hm.containsKey(r)){
         Counter v = (Counter)hm.get(r);
         System.out.println (r + ": " +v.i);
      }
    }
  }
} ///: