// 938. Range Sum of BST #include "leetcode.h" /* * given the 'root' of a binary search tree and two integers 'low' and 'high', * return the sum of values of all nodes with a value in the inclusive range * '(low, high)' */ struct TreeNode { int val; struct TreeNode *left; struct TreeNode *right; }; int rangeSumBST(struct TreeNode *root, int low, int high) { if (!root) return 0; else if (root->val >= low && root->val <= high) return root->val + rangeSumBST(root->left, low, high) + rangeSumBST(root->right, low, high); else return rangeSumBST(root->left, low, high) + rangeSumBST(root->right, low, high); }