将有序数组转变成平衡二叉查找树

import java.util.*;public class BinarySearchTreeTest {private static LinkedList<Integer> list = null;public static void convertToBst(LinkedList<Integer> s){list = s;TreeNode root = convertToBstHelp(0, list.size() -1);BinaryTreeTest.preOrderTraverse(root);}public static TreeNode convertToBstHelp(int start, int end){if (start > end)return null;int mid = (end + start)/2;TreeNode root = new TreeNode(list.get(mid));root.left = convertToBstHelp(start, mid -1);root.right = convertToBstHelp(mid + 1, end);return root;}public static void main(String[] args){LinkedList<Integer> s = new LinkedList<Integer>();for(int i = 0; i < 7; i++){s.add(i);}for(int i : s)System.out.println(i);convertToBst(s);}}