/** * Definition for a binary tree node. * public class TreeNode { * int val; * TreeNode left; * TreeNode right; * TreeNode(int x) { val = x; } * } */ public class Solution { public TreeNode sortedArrayToBST(int[] nums) { return toBST(nums,0,nums.length-1); } public TreeNode toBST(int[] nums, int start, int end){ if(start > end) return null; int mid = start+(end-start)/2; TreeNode root = new TreeNode(nums[mid]); root.left = toBST(nums,start,mid-1); root.right = toBST(nums,mid+1,end); return root; } }