Sum of Nodes with Even Grandparent Values
Given a binary tree root, return the sum of all node values whose grandparents have an even value.
Constraints
0 ≤ n ≤ 100,000wherenis the number of nodes inroot
https://binarysearch.com/problems/Sum-of-Nodes-with-Even-Grandparent-Values
ExamplesPermalink
Example 1Permalink
Input
- root =
Output
- answer =
15
Explanation
Nodes 6, 7, and 2 have an even value grandparent.
SolutionPermalink
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| /** | |
| * class Tree { | |
| * public: | |
| * int val; | |
| * Tree *left; | |
| * Tree *right; | |
| * }; | |
| */ | |
| int solveR(Tree *node, int *res) | |
| { | |
| if (!node) | |
| { | |
| return 0; | |
| } | |
| int left = solveR(node->left, res); | |
| int right = solveR(node->right, res); | |
| if (node->val % 2 == 0) | |
| { | |
| *res += left + right; | |
| } | |
| return (node->left ? node->left->val : 0) + (node->right ? node->right->val : 0); | |
| } | |
| int solve(Tree *root) | |
| { | |
| int res = 0; | |
| solveR(root, &res); | |
| return res; | |
| } |
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