LintCode 克隆二叉树题目分析代码

/**
 * Definition of TreeNode:
 * public class TreeNode {
 *     public int val;
 *     public TreeNode left, right;
 *     public TreeNode(int val) {
 *         this.val = val;
 *         this.left = this.right = null;
 *     }
 * }
 */
public class Solution {
    /**
     * @param root: The root of binary tree
     * @return root of new tree
     */
    public TreeNode cloneTree(TreeNode root) {
        // Write your code here
            if(root == null)  
        return null;  
  
    TreeNode dst = new TreeNode(0);  
    dst.val = root.val;  
    dst.left = cloneTree(root.left);  
    dst.right = cloneTree(root.right);  
  
    return dst;
    }
}