标签：style blog color io ar java for strong sp
Given a binary tree, flatten it to a linked list in-place.
For example,
Given
1
/ 2 5
/ \ 3 4 6
The flattened tree should look like: 1
2
3
4
5
6
If you notice carefully in the flattened tree, each node‘s right child points to the next node of a pre-order traversal.
/**
* Definition for binary tree
* public class TreeNode {
* int val;
* TreeNode left;
* TreeNode right;
* TreeNode(int x) { val = x; }
* }
*/
public class Solution {
public void flatten(TreeNode root) {
if(root==null||(root.left==null&&root.right==null))
{
return;
}
TreeNode left=root.left;
TreeNode right=root.right;
TreeNode last=root;
List<TreeNode>list=new LinkedList<TreeNode>();
if(right!=null)
{
list.add(0,right);
}
if(left!=null)
{
list.add(0,left);
}
while(list.size()>0)
{
TreeNode p=list.get(0);
list.remove(0);
last.left=null;
last.right=p;
last=p;
left=last.left;
right=last.right;
if(right!=null)
{
list.add(0,right);
}
if(left!=null)
{
list.add(0,left);
}
}
}
}Flatten Binary Tree to Linked List
标签：style blog color io ar java for strong sp
原文地址：http://blog.csdn.net/jiewuyou/article/details/40182239
