Convert Sorted Array to Binary Search Tree

Given an array where elements are sorted in ascending order, convert it to a height balanced BST.

 

/**
 * 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 solve(nums, 0, nums.length-1);
    }

	private TreeNode solve(int[] nums, int s, int e) {
		if (s > e) {
			return null;
		}
		int mid = (s+e)/2;
		TreeNode root = new TreeNode(nums[mid]);
		root.left = solve(nums, s, mid-1);
		root.right = solve(nums, mid+1, e);
		return root;
	}
}