mycode 93.97%
""" # Definition for a Node. class Node(object): def __init__(self, val, left, right, next): self.val = val self.left = left self.right = right self.next = next """ class Solution(object): def connect(self, root): if not root: return None if root and root.left: root.left.next = root.right if root.next != None: #print(root.val,root.next) root.right.next = root.next.left self.connect(root.left) self.connect(root.right) return root
参考：
其实第二个if可以只写root.left，这样阔以快一丢丢啦
class Solution(object): def connect(self, root): """ :type root: Node :rtype: Node """ if not root: return None if root.left: root.left.next = root.right if root.next: root.right.next = root.next.left self.connect(root.left) self.connect(root.right) return root
leetcode-mid-Linked list- 116. Populating Next Right Pointers in Each Node
原文：https://www.cnblogs.com/rosyYY/p/10968584.html