Description

For the given binary tree, return a deep copy of it.

Example

Given a binary tree:

     1
   /    2    3
 / 4   5

return the new binary tree with same structure and same value:

     1
   /    2    3
 / 4   5

解題：鏈表復制。遞歸解法比較簡單，代碼如下：

/**
 * 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 new_root = new TreeNode(root.val);
        new_root.left 
 
= cloneTree(root.left);
        new_root.right = cloneTree(root.right);
        return new_root;
    }
}

375. Clone Binary Tree【LintCode java】