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BJP5 Exercise 17.1: countLeftNodes

Language/Type: Java binary trees implementing IntTree
Related Links:
Author: Robert Baxter (on 2019/09/19)

Write a method countLeftNodes that returns the number of left children in the tree. A left child is a node that appears as the root of the left-hand subtree of another node. An empty tree has 0 left nodes. For example, the following tree has four left children (the nodes storing the values 5, 1, 4, and 7): 

          +---+
          | 3 |
          +---+
         /     \
     +---+     +---+
     | 5 |     | 2 |
     +---+     +---+
    /         /     \
+---+     +---+     +---+
| 1 |     | 4 |     | 6 |
+---+     +---+     +---+
         /
     +---+
     | 7 |
     +---+

Assume that you are adding this method to the IntTree class as defined below: 

public class IntTree {
    private IntTreeNode overallRoot;
    ...
}
Type your solution here:


This is a partial class problem. Submit code that will become part of an existing Java class as described. You do not need to write the complete class, just the portion described in the problem.

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