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BJP4 Exercise 17.11: numberNodes

Language/Type: Java binary trees implementing IntTree
Related Links:
Author: Robert Baxter (on 2016/09/08)

Write a method numberNodes that changes the data stored in a binary tree, assigning sequential integers starting with 1 to each node so that a pre-order traversal will produce the numbers in order(1, 2, 3, etc.). For example, given the tree referenced by tree below at left, the call of tree.numberNodes(); would overwrite the existing data assigning the nodes values from 1 to 6 so that a pre-order traversal of the tree would produce 1, 2, 3, 4, 5, 6.

Before Call After Call 
          +---+
          | 7 |
          +---+
         /     \
     +---+     +---+
     | 3 |     | 9 |
     +---+     +---+
    /     \         \
+---+     +---+     +---+
| 9 |     | 2 |     | 0 |
+---+     +---+     +---+

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

You are not to change the structure of the tree. You are simply changing the values stored in the data fields. Your method should return a count of how many nodes were in the tree.

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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