Given an array where elements are sorted in ascending order, convert it to a height balanced BST.
/**
* Definition for a binary tree node.
* struct TreeNode {
* int val;
* TreeNode *left;
* TreeNode *right;
* TreeNode(int x) : val(x), left(NULL), right(NULL) {}
* };
*/
class Solution {
public:
TreeNode* sortedArrayToBST(vector<int>& nums) {
return sortedArrayToBST(nums.begin(), nums.end());
}
template<typename RandomAccessIterator>
TreeNode* sortedArrayToBST (RandomAccessIterator first, RandomAccessIterator last) {
const auto length = distance(first, last);
if (length <= 0) return nullptr;
auto mid = first + length / 2;
TreeNode *root = new TreeNode(*mid);
root->left = sortedArrayToBST(first, mid);
root->right = sortedArrayToBST(next(mid), last);
return root;
}
};