Hi i`m new to java however i have been given a piece of coursework. What it wants me to do is basically store strings in a binery tree however when i test it my count method does not seem to be working what its supposed to do is see how many times a particular string appearers in the tree.Is it possible someone can modify my count method so its correct thanks.

import java.util.*;
//node of the binary tree
class WordStore {   
  String word;
  WordStore left;
  WordStore right;
  int b;
  WordStore root;

  WordStore() {           
    word = null;
    left = null;
    right = null;
  }

 public  WordStore(String  word) {

    this.word = word;
    left = null;
    right = null;
    root = null;
  }
public WordStore(int a)//doenst compile without it
  {

   b = a;
   }

   //binary tree





//insert a node into the tree
  public void add(String word) 
{
    WordStore current = root;
    WordStore prev = current;
    if (root == null) 
    {
      root = new WordStore(word);
    }

    else 
    {
      boolean insert = false;
      while (insert == false)
     {

        prev = current;
        if (word.compareTo(current.word) < 0) 
        {
          if (current.left == null)
     {
            current.left = new WordStore(word);
            insert = true;
          }
          current = current.left;

             }
        else 
    {
          if (current.right == null) 
        {
                current.right = new WordStore(word);
                insert = true;
            }
          current = current.right;
        }

            }

    }

  }
  //delete a node with a word
 public void remove(WordStore node, String word) {
   //   Task2 temp  ,prev = null;

     //   boolean deleted = true;
        WordStore current = root;
            WordStore prev = current;

        if(node != null && node.word.equals(word)){
            if(node.right==null)
                node=node.left;
            else if (node.left==null)
                node =node.right;
            else{
                current =node.left;
                while(current.right != null)
                    current = current.right;
                current.right=node.right;
                node = node.left;
            }
            if (node==root)
                root = node;
            else if (prev.left == root )
                prev.left = node;
            else prev.right = node ;
        }

    else if (root != null)
            System.out.println(word + "is not in the tree ");
        else  System.out.println("the tree is empty");



    }

// public int count(String word) 

    public int count(String word) 
    {  int i=0;
        WordStore current = root;
        WordStore prev = current;
        while (current != null) 
        {
          if (word.compareTo(current.word) > 0) 
          {
        prev = current;
        current = current.right;
        i++;
          }
          else if (word.compareTo(current.word) < 0) 
          {
        prev = current;
        current = current.left;
        i++;
          }
          else if (word.compareTo(current.word) == 0) 
          {

        break;
          }



      }

        return i;   



    }

}

A simpler way to do this would be to keep another integer (lets say count) and each time you add to the tree increment count. Also each time you remove an item from the tree decrease the count.

Cheers

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