完全二叉树插入

/**题目：给完全二叉树插入一个节点，插完后保证还是完全二叉树
* @author ShaoCheng
* @version 1.0 2015-9-24
*/

class TreeNode{
int val;
TreeNode left, right;
TreeNode(int key){
val = key;
}
}

public class Main {
public static void main(String[] args){
TreeNode p1 = new TreeNode(1);
TreeNode p2 = new TreeNode(2);
TreeNode p3 = new TreeNode(3);
TreeNode p4 = new TreeNode(4);
p1.left = p2;
p1.right = p3;
p2.left = p4;

TreeNode node = new TreeNode(100);
TreeNode root = insertBinary(p1, node);
printTree(root);
}

//中序遍历
public static void printTree(TreeNode root){
if(root == null)
return;
System.out.println(root.val);
printTree(root.left);
printTree(root.right);
}

public static TreeNode insertBinary(TreeNode root, TreeNode node){
if(root == null)
return node;
else if(node == null)
return root;
if(root.left == null){
root.left = node;
return root;
}
else if(root.right == null){
root.right = node;
return root;
}

int lrh = 0;
int rrh = 0;
TreeNode pNode = root.left;
while(pNode != null){
lrh++;
pNode = pNode.right;
}

pNode = root.right;
while(pNode != null){
rrh++;
pNode = pNode.left;
}

if(lrh != rrh){
insertBinary(root.right, node);
}
else
insertBinary(root.left, node);
return root;
}
}