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 1:
Input: root = [3,4,5,1,2], subRoot = [4,1,2]
Output: true
Example 2:
Input: root = [3,4,5,1,2,null,null,null,null,0], subRoot = [4,1,2]
Output: false
Solution
class TreeNode:
def __init__(self, val=0, left=None, right=None):
self.val = val
self.left = left
self.right = right
class Solution:
def isSubtree(self, root: Optional[TreeNode], subRoot: Optional[TreeNode]) -> bool:
if not subRoot:
return True
if not root:
return False
if self.same_tree(root, subRoot):
return True
return self.isSubtree(root.left, subRoot) or self.isSubtree(root.right, subRoot)
def same_tree(self, root, subRoot):
if not root and not subRoot:
return True
if root and subRoot and root.val == subRoot.val:
return self.same_tree(root.left, subRoot.left) and self.same_tree(root.right, subRoot.right)
return False