572_Subtree_of_Another_Tree.py

# 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 isSubtree(self, root: Optional[TreeNode], subRoot: Optional[TreeNode]) -> bool:
        if root is None:
            return False

        if self.isSameTree(root, subRoot):
            return True

        return (self.isSubtree(root.left, subRoot) or
                self.isSubtree(root.right, subRoot))

    def isSameTree(self, p: Optional[TreeNode], q: Optional[TreeNode]) -> bool:
        if p == None:
            return q == None
        if q == None:
            return p == None

        if p.val != q.val:
            return False

        if self.isSameTree(p.left, q.left) == False:
            return False
        if self.isSameTree(p.right, q.right) == False:
            return False

        return True