Day 5 LeetCode

Day 5 Task:

Solutions:

'''
Approach 1: Iterative approach 
-> we check if there is a root in the first place, if not, we return none. 
-> then, while a root node exists, 
we check if the value given is less than the root node value, 
if yes -> we move the root to the left (left subtree), similarly we 
see if the value given is greater than the root node value, 
if yes -> we move the root to the right (right subtree)
now if the root.val and val are equal (else condition) ==> return the root.
'''

class Solution(object):
    def searchBST(self, root, val):

        if not root: return None
        while root:
            if val<root.val: root = root.left
            elif val>root.val: root = root.right
            else: return(root)

'''
Approach 2: Recursive Approach
The concept is the same, rather than changing the root value here, 
we recursively call the function with the left/right subtree as root
till we find the value
'''
class Solution(object):
    def searchBST(self, root, val):
        
        if not root: return None
        
        if val<root.val: return self.searchBST(root.left,val)
        elif val>root.val: return self.searchBST(root.right,val)
        else: return(root)