leetcode 938. 二叉搜索树的范围和

给定二叉搜索树的根结点 root，返回值位于范围 [low, high] 之间的所有结点的值的和。

示例 1：

输入：root = [10,5,15,3,7,null,18], low = 7, high = 15
输出：32
示例 2：

输入：root = [10,5,15,3,7,13,18,1,null,6], low = 6, high = 10
输出：23

提示：

树中节点数目在范围 [1, 2 * 104] 内
1 <= Node.val <= 105
1 <= low <= high <= 105
所有 Node.val 互不相同

/**
 * Definition for a binary tree node.
 * struct TreeNode {
 *     int val;
 *     TreeNode *left;
 *     TreeNode *right;
 *     TreeNode() : val(0), left(nullptr), right(nullptr) {}
 *     TreeNode(int x) : val(x), left(nullptr), right(nullptr) {}
 *     TreeNode(int x, TreeNode *left, TreeNode *right) : val(x), left(left), right(right) {}
 * };
 */
class Solution {
public:
    int sum = 0;
    int rangeSumBST(TreeNode* root, int low, int high) {
       queue<TreeNode*> q;
       if(root != NULL) q.push(root);
       while(!q.empty()){
           TreeNode* t = q.front();
           int val = t->val;
           q.pop();
           if(val >= low && val <= high) sum+=val;
           if(t->left != NULL) q.push(t->left);
           if(t->right != NULL) q.push(t->right);
       }
       return sum;
    }
};

leetcode 938. 二叉搜索树的范围和

原文：https://www.cnblogs.com/superkcl/p/14744640.html