LeetCode 100. Same Tree

November 20, 2024

Today I chose an easy problem since I had a late day at work and gym afterwards.

Solution

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1from collections import deque
2
3# Definition for a binary tree node.
4# class TreeNode:
5#     def __init__(self, val=0, left=None, right=None):
6#         self.val = val
7#         self.left = left
8#         self.right = right
9class Solution:
10    def isSameTree(self, p: Optional[TreeNode], q: Optional[TreeNode]) -> bool:
11        pQ = deque([p])
12        qQ = deque([q])
13
14        while pQ and qQ:
15            nodeP = pQ.popleft()
16            nodeQ = qQ.popleft()
17            if nodeP and nodeQ and nodeP.val != nodeQ.val:
18                return False
19            elif (nodeP is None) != (nodeQ is None):
20                return False
21
22            if nodeP:
23                pQ.append(nodeP.left)
24                pQ.append(nodeP.right)
25            if nodeQ:
26                qQ.append(nodeQ.left)
27                qQ.append(nodeQ.right)
28
29        if not pQ and not qQ:
30            return True
31        
32        return False

Time complexity is O(n) = n and space complexity is O(n).

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