100. Same Tree

문제

Given two binary trees, 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:     1         1
          / \       / \
         2   3     2   3

        [1,2,3],   [1,2,3]

Output: true

Example 2:

Input:     1         1
          /           \
         2             2

        [1,2],     [1,null,2]

Output: false

Example 3:

Input:     1         1
          / \       / \
         2   1     1   2

        [1,2,1],   [1,1,2]

Output: false

풀이

class Solution:
    def isSameTree(self, p: TreeNode, q: TreeNode) -> bool:        
        if p==None and q==None :
            return True

        if p==None or q==None :
            return False

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