100. Same Tree

Easy

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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

Solution:

# 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 isSameTree(self, p: TreeNode, q: TreeNode) -> bool:
if p == None and q == None:
return True
elif p == None and q != None:
return False
elif p != None and q == None:
return False
elif p.val != q.val:
return False
else:
return self.isSameTree(p.left, q.left) and self.isSameTree(p.right, q.right)

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