Given an array where elements are sorted in ascending order, convert it to a height balanced BST.
/** * Definition for binary tree * struct TreeNode { * int val; * TreeNode *left; * TreeNode *right; * TreeNode(int x) : val(x), left(NULL), right(NULL) {} * }; */ class Solution { public: TreeNode * CreateNode(vector<int>&vals,int start,int end){ if(start>end)return NULL; int mid=(start+end)/2; TreeNode* ret=new TreeNode(vals[mid]); ret->left=CreateNode(vals,start,mid-1); ret->right=CreateNode(vals,mid+1,end); } TreeNode *sortedArrayToBST(vector<int> &num) { // Start typing your C/C++ solution below // DO NOT write int main() function return CreateNode(num,0,num.size()-1); } };