// Erika Wolfe, CSE 143
// This class represents a tree of integers
public class IntTree {
   private IntTreeNode overallRoot;
   
   // Constructs a tree with default numbers
   public IntTree() {
      overallRoot = null; 
   }
   
   // prints the numbers in this tree in a pre-order fashion.
   public void print() {
      print(overallRoot);
   }
   
   // prints the numbers of the subtree beginning at root 
   // using a pre-order traversal.
   private void print(IntTreeNode root) {
      if (root != null) {
         System.out.print(root.data + " ");

         // print the left
         print(root.left); 
         // print the right
         print(root.right);     
      }
   }
   
   // Returns the number of numbers in this tree.
   public int size() {
      return size(overallRoot);
   }
   
   // Returns the number of nodes in the tree starting at root.
   private int size(IntTreeNode root) {
      if (root == null) {
         return 0;
      } else {
         int leftSize = size(root.left);
         int rightSize = size(root.right);
         return 1 + leftSize + rightSize;
      }
   }
}