One Leetcode per day-654. The largest binary tree [Tree｜Recursion]

It is a very simple recursive idea.

/**
 * Definition for a binary tree node.
 * public class TreeNode {
 *     int val;
 *     TreeNode left;
 *     TreeNode right;
 *     TreeNode() {}
 *     TreeNode(int val) { this.val = val; }
 *     TreeNode(int val, TreeNode left, TreeNode right) {
 *         this.val = val;
 *         this.left = left;
 *         this.right = right;
 *     }
 * }
 */
class Solution {
    
    
    public TreeNode constructMaximumBinaryTree(int[] nums) {
    
    
        if(nums.length==0) return null;
        int max_index = -1;
        int max_data = Integer.MIN_VALUE;
        for(int i=0;i<nums.length;i++){
    
    
            if(nums[i]>max_data){
    
    
                max_index = i;
                max_data = nums[i];
            }
        }
        
        TreeNode root = new TreeNode(max_data);
        root.left = constructMaximumBinaryTree(Arrays.copyOfRange(nums,0,max_index));
        root.right = constructMaximumBinaryTree(Arrays.copyOfRange(nums,max_index+1,nums.length));
        return root;
    }
}