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: trueExample 2:
Input: 1 1
/ \
2 2
[1,2], [1,null,2]
Output: falseExample 3:
Input: 1 1
/ \ / \
2 1 1 2
[1,2,1], [1,1,2]
Output: false这一题主要是考查二叉树的前向遍历
# Definition for a binary tree node.
# class TreeNode:
# def __init__(self, x):
# self.val = x
# self.left = None
# self.right = None
class Solution:
def isSameTree(self, p: TreeNode, q: TreeNode) -> bool:
result1=[]
result2=[]
def pre_order(ptr,result):
if ptr:
result.append(ptr.val)
pre_order(ptr.left,result)
pre_order(ptr.right,result)
else:
result.append('None')
pre_order(p,result1)
pre_order(q,result2)
if result1==result2:
return True
return False
