牛客网每日一练

# class TreeNode:
#     def __init__(self, x):
#         self.val = x
#         self.left = None
#         self.right = None

#
# 
# @param root TreeNode类 
# @return int整型一维数组
#
class Solution:
    def inorderTraversal(self , root ):
        if not root:
            return[]
        left = self.inorderTraversal(root.left)
        right = self.inorderTraversal(root.right)
        return left + [root.val] +right
        # write code here

给出一棵二叉树，返回这棵树的中序遍历

例如：

给出的二叉树为{1,#,2,3},

1

\

2

/

3

返回[1,3,2].