Leetcode 938. 二叉搜尋樹的範圍和（DAY 2)

原題題目

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程式碼實現

/**
 * Definition for a binary tree node.
 * struct TreeNode {
 *     int val;
 *     struct TreeNode *left;
 *     struct TreeNode *right;
 * };
 */


int rangeSumBST(struct TreeNode* root, int low, int high){
    if(!root)
        return 0;
    if(root->val <= high && root->val>= low)
        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);
}