-
Notifications
You must be signed in to change notification settings - Fork 3
/
Solution.py
31 lines (25 loc) · 981 Bytes
/
Solution.py
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
# 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 longestUnivaluePath(self, root: TreeNode) -> int:
self.ans = 0
def arrow_len(node):
if not node:
return 0
# 재귀
left_length, right_length = arrow_len(node.left), arrow_len(node.right)
# 다르면 0임을 의미
left_arrow = right_arrow = 0
if node.left and node.left.val == node.val:
left_arrow = left_length + 1 # 같으면 값 증가
if node.right and node.right.val == node.val:
right_arrow = right_length + 1
# 반환하기 전에 값 갱신
self.ans = max(self.ans, left_arrow + right_arrow)
return max(left_arrow, right_arrow)
arrow_len(root)
return self.ans