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程式語言 - LeetCode - C++ - 108. Convert Sorted Array to Binary Search Tree

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參考資訊：
https://www.cnblogs.com/grandyang/p/4295245.html

題目：


解答：

/**
 * 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:
    TreeNode* sortedArrayToBST(vector<int>& nums) {
        auto dfs = [&](this auto&& dfs, int l, int r) -> TreeNode* {
            if (l > r) {
                return NULL;
            }

            int m = l + ((r - l) >> 1);
            TreeNode *t = new TreeNode(nums[m]);

            t->left = dfs(l, m - 1);
            t->right = dfs(m + 1, r);
            return t;
        };

        return dfs(0, nums.size() - 1);
    }
};