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BJP4 Exercise 17.6: printLeaves

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

Write a method printLeaves that outputs the leaves of a binary tree from right to left. More specifically, the leaves should be printed in the reverse order that they would be printed using any of the standard traversals. For example, if a variable tree stores a reference to the following tree: 

          +---+
          | 2 |
          +---+
         /     \
     +---+     +---+
     | 8 |     | 1 |
     +---+     +---+
    /         /     \
+---+     +---+     +---+
| 0 |     | 7 |     | 6 |
+---+     +---+     +---+
         /               \
     +---+               +---+
     | 4 |               | 9 |
     +---+               +---+

Then the call of t.printLeaves(); should produce the following output: 

leaves: 9 4 0

If the tree does not have any leaves (an empty tree), simply print: 

no leaves

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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