forked from DaleStudy/leetcode-study
-
Notifications
You must be signed in to change notification settings - Fork 0
Expand file tree
/
Copy pathJeehay28.ts
More file actions
30 lines (24 loc) · 742 Bytes
/
Jeehay28.ts
File metadata and controls
30 lines (24 loc) · 742 Bytes
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
class TreeNode {
val: number;
left: TreeNode | null;
right: TreeNode | null;
constructor(val?: number, left?: TreeNode | null, right?: TreeNode | null) {
this.val = val === undefined ? 0 : val;
this.left = left === undefined ? null : left;
this.right = right === undefined ? null : right;
}
}
// TC: O(n)
// SC: O(n)
function maxPathSum(root: TreeNode | null): number {
let maxSum = -Infinity;
const dfs = (node: TreeNode | null) => {
if (!node) return 0;
const leftMax = Math.max(dfs(node.left), 0);
const rightMax = Math.max(dfs(node.right), 0);
maxSum = Math.max(node.val + leftMax + rightMax, maxSum);
return node.val + Math.max(leftMax, rightMax);
};
dfs(root);
return maxSum;
}