题目链接:https://leetcode-cn.com/problems/convert-sorted-array-to-binary-search-tree/
题目如下:
/**
* 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) {
return dfs(nums,0,nums.size()-1);
}
TreeNode* dfs(vector<int>& nums,int l,int r){
if(l>r) return nullptr;
int k=l+(r-l)/2;
int root_val=nums[k];
TreeNode* root=new TreeNode(root_val);
root->left=dfs(nums,l,k-1);
root->right=dfs(nums,k+1,r);
return root;
}
};