def sorted_list_to_bst(left, right):
if left > right:
return None
mid = left + (right - left) // 2
left_node = sorted_list_to_bst(left, mid - 1)
new_node = TreeNode(self.__class__.head.val)
new_node.left = left_node
self.__class__.head = self.__class__.head.next
new_node.right = sorted_list_to_bst(mid + 1, right)
return new_node
def sorted_list_to_bst(left, right):
if left > right:
return None
mid = left + (right-left)//2
left_node = sorted_list_to_bst(left, mid-1)
new_node = TreeNode(self.__class__.head.val)
new_node.left = left_node
self.__class__.head = self.__class__.head.next
new_node.right = sorted_list_to_bst(mid+1, right)
return new_node
def sortedArrayToBST(self, nums):
"""
:type nums: List[int]
:rtype: TreeNode
"""
if not nums:
return None
mid = len(nums)//2
node = TreeNode(nums[mid])
node.left = self.sortedArrayToBST(nums[:mid])
node.right = self.sortedArrayToBST(nums[mid+1:])
return node