﻿ Python Binary Search Tree: Find the kth smallest element in a given a binary search tree(BST) - w3resource

# Python Binary Search Tree: Find the kth smallest element in a given a binary search tree (BST)

## Python Binary Search Tree: Exercise-6 with Solution

Write a Python program to find the kth smallest element in a given a binary search tree.

Sample Solution:

Python Code:

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

def kth_smallest(root, k):
stack = []
while root or stack:
while root:
stack.append(root)
root = root.left
root = stack.pop()
k -= 1
if k == 0:
break
root = root.right
return root.val

root = TreeNode(8)
root.left = TreeNode(5)
root.right = TreeNode(14)
root.left.left = TreeNode(4)
root.left.right = TreeNode(6)
root.left.right.left = TreeNode(8)
root.left.right.right = TreeNode(7)
root.right.right = TreeNode(24)
root.right.right.left = TreeNode(22)

print(kth_smallest(root, 2))
print(kth_smallest(root, 3))
```
```

Sample Output:

```5
8
```

Flowchart: Python Code Editor: