码迷,mamicode.com
首页 > 其他好文 > 详细

leetcode--Populating Next Right Pointers in Each Node II

时间:2014-06-05 13:26:37      阅读:335      评论:0      收藏:0      [点我收藏+]

标签:c   class   blog   code   java   a   

Follow up for problem "Populating Next Right Pointers in Each Node".

What if the given tree could be any binary tree? Would your previous solution still work?

Note:

  • You may only use constant extra space.

 

For example,
Given the following binary tree,

         1
       /        2    3
     / \        4   5    7

 

After calling your function, the tree should look like:

         1 -> NULL
       /        2 -> 3 -> NULL
     / \        4-> 5 -> 7 -> NULL

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
public class Solution {
    public void connect(TreeLinkNode root) {
        if(root != null){
            root.next = null;
            TreeLinkNode topLevel = root;
            TreeLinkNode nextLevelHead = null;
            TreeLinkNode node = null;
            while(topLevel != null){
                //looking for the head of next level
                while(topLevel != null && nextLevelHead == null){
                    if(topLevel.left != null){
                        nextLevelHead = topLevel.left;
                        node = nextLevelHead;
                    }
                    if(topLevel.right != null){
                        if(node == null){
                            nextLevelHead = topLevel.right;
                            node = nextLevelHead;
                        }
                        else{
                            node.next = topLevel.right;
                            node = node.next;
                        }
                    }
                     
                    topLevel = topLevel.next;
                }
                 
                while(topLevel != null){
                    if(topLevel.left != null){
                        node.next = topLevel.left;
                        node = node.next;
                    }
                    if(topLevel.right != null){
                        node.next = topLevel.right;
                        node = node.next;
                    }
                    topLevel = topLevel.next;
                }
                 
                if(node != null){
                    node.next = null;
                    node = node.next;
                }
                topLevel = nextLevelHead;
                nextLevelHead = null;
            }
        }
    }
}

  

leetcode--Populating Next Right Pointers in Each Node II,布布扣,bubuko.com

leetcode--Populating Next Right Pointers in Each Node II

标签:c   class   blog   code   java   a   

原文地址:http://www.cnblogs.com/averillzheng/p/3769567.html

(0)
(0)
   
举报
评论 一句话评论(0
登录后才能评论!
© 2014 mamicode.com 版权所有  联系我们:gaon5@hotmail.com
迷上了代码!