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100. Same Tree

Easy

Given the roots of two binary trees p and q, write a function to check if they are the same or not.

Two binary trees are considered the same if they are structurally identical, and the nodes have the same value.

Example 1:

Input: p = [1,2,3], q = [1,2,3]
Output: true

Example 2:

Input: p = [1,2], q = [1,null,2]
Output: false

Example 3:

Input: p = [1,2,1], q = [1,1,2]
Output: false

Constraints:

  • The number of nodes in both trees is in the range [0, 100].
  • -10^4 <= Node.val <= 10^4

Solution

class Solution:
    def isSameTree(self, p: Optional[TreeNode], q: Optional[TreeNode]) -> bool:
        if p is None and q is None:
            return True
        if p is None or q is None:
            return False

        return (
            p.val == q.val
            and self.isSameTree(p.left, q.left)
            and self.isSameTree(p.right, q.right)
        )


class TreeNode:
    def __init__(self, val=0, left=None, right=None):
        self.val = val
        self.left = left
        self.right = right