111.二叉树的最小深度.py

#
# @lc app=leetcode.cn id=111 lang=python3
#
# [111] 二叉树的最小深度
#
# Definition for a binary tree node.
# class TreeNode:
#     def __init__(self, x):
#         self.val = x
#         self.left = None
#         self.right = None

class Solution:
    def minDepth(self, root: TreeNode) -> int:
        if root == None:
            return 0
        while self.root and self.right: