111. Minimum Depth of Binary Tree

Given a binary tree, find its minimum depth.

The minimum depth is the number of nodes along the shortest path from the root node down to the nearest leaf node.

 1 # Definition for a binary tree node.
 2 # class TreeNode(object):
 3 #     def __init__(self, x):
 4 #         self.val = x
 5 #         self.left = None
 6 #         self.right = None
 7 
 8 class Solution(object):
 9     def minDepth(self, root):
10         """
11         :type root: TreeNode
12         :rtype: int
13         """
14         if root == None:
15             return 0
16         if root.left==None or root.right==None:
17             return self.minDepth(root.left)+self.minDepth(root.right)+1
18         return 1 + min(self.minDepth(root.left),self.minDepth(root.right))

posted on 2017-03-15 18:08 Ci_pea 阅读(92) 评论(0) 编辑收藏举报