程序员面试金典 - 面试题 04.02. 最小高度树（二叉搜索树中序遍历）

      0 
     / \ 
   -3   9 
   /   / 
 -10  5 

class Solution {
public:
    TreeNode* sortedArrayToBST(vector<int>& nums) {
    	return build(nums,0,nums.size()-1);
    }

    TreeNode* build(vector<int>& nums, int l, int r)
    {
    	if(l > r)
    		return NULL;
    	int mid = l+((r-l)>>1);
    	TreeNode* root = new TreeNode(nums[mid]);
    	root->left = build(nums,l,mid-1);
    	root->right = build(nums,mid+1,r);
    	return root;
    }
};