题目:
Given an array where elements are sorted in ascending order, convert it to a height balanced BST.
程序:
class Solution {
public:
TreeNode *sortedArrayToBST(vector<int> &num)
{
return ArrayToBST(num,0,num.size());
}
TreeNode *ArrayToBST(vector<int> &num,int begin,int end)
{
if(begin >= end)
return nullptr;
int middle = (end+begin)>>1;
TreeNode *root = new TreeNode(num[middle]);
root->left = ArrayToBST(num,begin,middle);
root->right = ArrayToBST(num,middle+1,end);
return root;
}
};