Leetcode 572. Subtree of Another Tree. Python (Recursive)

572. Subtree of Another Tree

Given the roots of two binary trees root and subRoot, return true if there is a subtree of root with the same structure and node values of subRoot and false otherwise.

A subtree of a binary tree tree is a tree that consists of a node in tree and all of this node's descendants. The tree tree could also be considered as a subtree of itself.

Example :

Input: root = [3,4,5,1,2], subRoot = [4,1,2]
Output: true

SOLUTION:

class Solution:
    def isSubtree(self, r: Optional[TreeNode], sr: Optional[TreeNode]) -> bool:
        if not sr: return True
        if not r: return False
        
        if self.sameTree(r,sr):
            return True
        
        return (self.isSubtree(r.left, sr) or
        self.isSubtree(r.right, sr))
    
    def sameTree(self, r, sr):
        if not r and not sr:
            return True
        if r and sr and r.val == sr.val:
            return (self.sameTree(r.left, sr.left) and
            self.sameTree(r.right, sr.right))
        return False

Explaination :

Comments

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