# Definition for a binary tree node.
# class TreeNode:
# def __init__(self, val=0, left=None, right=None):
# self.val = val
# self.left = left
# self.right = right
class Solution:
def kthSmallest(self, root: Optional[TreeNode], k: int) -> int:
res = []
def inorder(root, res):
if root is None:
return
res.append(root.val)
inorder(root.left, res)
inorder(root.right, res)
inorder(root, res)
res.sort()
return res[k - 1]
# Definition for a binary tree node.
# class TreeNode:
# def __init__(self, val=0, left=None, right=None):
# self.val = val
# self.left = left
# self.right = right
class Solution:
def kthSmallest(self, root: Optional[TreeNode], k: int) -> int:
s = deque()
current = root
count = 0
while s or current:
while(current):
s.append(current)
current = current.left
current = s.pop()
count +=1
if count == k:
return current.val
current = current.right