Lintcode_177_ converting a sorted array to a two-fork search tree with a minimum height

Converts a sorted array into a two-prong search tree with the smallest height

• Describe
• Notes
• Data
• Evaluation

Give a sorted array (from small to large) and convert it to a binary tree with the smallest height.

Precautions

There may exist multiple valid solutions and return any of them.

Have you ever encountered this problem in a real interview? YesWhich company is asking you this question?LinkedinAirbnbamazon cryptic Studios Span class= "BTN Btn-xs btn-white Company" >dropbox epic Systems tinyco hedvig facebook google uber yelp apple yahoo bloomberg zenefits twitter microsoft snapchat Thank you for your feedback Sample Example

Give the array [1,2,3,4,5,6,7] , return

     4   /     2     6 / \    / 1   3  5   7


这道题本来都打算放弃了，现在倒回头来重新看了一遍，做过树状数组和线段树的一些练习后是容易多了。

/** * Definition of TreeNode: * Class TreeNode {* Public: *     int val; *     TreeNode *left, *right; *     TreeNode (int val) {*         this->val = val; *         this->left = This->right = NULL; *     } *} */class Solution {public:    / *     * @param a:an integer array     * @return: A tree Node     *    /TreeNode * SORTEDARRAYTOBST (vector<int> &A mp A) {        //write your code        here if (! A.size ())            return NULL;        int R=a.size ()-1;        int l=0;        int m= (l+r) >>1;        TreeNode *root=subnode (a,l,r);        return root;    }    TreeNode *subnode (vector<int> a,int l,int R)    {        if (l>r)            return NULL;        int m= (l+r) >>1;        TreeNode *root=new TreeNode (a[m]);        Root->left=subnode (a,l,m-1);        Root->right=subnode (a,m+1,r);        return root;    }};

　　

Lintcode_177_ converting a sorted array to a two-fork search tree with a minimum height