leetcode_111. Minimum Depth of Binary Tree 二叉树的最小深度

题目：

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.

题意：

给定一棵二叉树，求该二叉树的最小深度并返回

代码：

# Definition for a binary tree node.
# class TreeNode(object):
#     def __init__(self, x):
#         self.val = x
#         self.left = None
#         self.right = None


class Solution(object):
    def getdepth(self, root, depth, result):
        """
        :type root: TreeNode
        :type depth: int
        :type result: list
        :rtype: int
        """
        depth += 1
        
        if root.left == None and root.right == None :
            return result.append(depth)
        else :
            if  root.left != None :
                tl_depth = copy.deepcopy(depth)
                self.getdepth(root.left, tl_depth, result)
            if  root.right != None :
                tr_depth = copy.deepcopy(depth)
                self.getdepth(root.right, tr_depth, result)
        
    
    
    def minDepth(self, root):
        """
        :type root: TreeNode
        :rtype: int
        """
        
        if root == None :
            return 0
        else :
            depth = 0
            result = []
            self.getdepth(root, depth, result)
            return min(result)
            

笔记：

1、还是一个深度优先遍历的题