using System;

public class BinNode<T> {

    private BinNode<T> left;

    private T value;

    private BinNode<T> right;

    public BinNode(T x) {

        this.left = null;

        this.value = x;

        this.right = null;

    }

​

    public BinNode(BinNode<T> left, T x, BinNode<T> right) {

        this.left = left;

        this.value = x;

        this.right = right;

    }

​

    public T getValue() {

        return this.value;

    }

​

    public void setValue(T x) {

        this.value = x;

    }

​

    public BinNode<T> getLeft() {

        return this.left;

    }

​

    public BinNode<T> getRight() {

        return this.right;

    }

​

    public void setLeft(BinNode<T> left) {

        this.left = left;

    }

​

    public void setRight(BinNode<T> right) {

        this.right = right;

    }

​

    public bool hasRight() {

        return this.right != null;

    }

​

    public bool hasLeft() {

        return this.left != null;

    }

​

    public override String ToString() {

        return this.value.ToString();

    }

}

​

public class Program

{

    public static int CountLetter(BinNode<String> tr, char ch){

        if(tr == null){

            return 0;

        }

        int count = 0;

        for(int i = 0; i<tr.getValue().Length; i++){

            if(ch == tr.getValue()[i]){

                count ++;

            }

        }

        return count + CountLetter(tr.getLeft(),ch) + CountLetter(tr.getRight(),ch);

    }

    public void PritAlphaBethCount(BinNode<String> tr){

        if(tr==null){

            Console.WriteLine("");

        }

        for(char c = 'a'; c<='z'; c++){

            Console.WriteLine(CountLetter(tr,c));

        }

    }

    public static void Main()

    {

        Console.WriteLine("Hello World");

    }

}