convert-sorted-array-to-binary-search-tree.py

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


class Solution:
    def sortedArrayToBST(self, nums):
        """
        :type nums: List[int]
        :rtype: TreeNode
        """
        if not nums:
            return None
        else:
            m = len(nums) // 2
            root = TreeNode(nums[m])
            root.left = self.sortedArrayToBST(nums[:m])
            root.right = self.sortedArrayToBST(nums[m + 1 :])
            return root