LeetCode-Easy刷题(23) Convert Sorted Array to Binary Search Tree

Posted 2022-05-31 当以乐

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

将有序数组转化为二分查找树

 public TreeNode sortedArrayToBST(int[] nums) 

        return toBSTHelp(nums, 0, nums.length-1);
    


    public TreeNode toBSTHelp(int[] nums,int start,int end)

        if(start>end)
            return null;
        

        int mid = (start+end)/2;

        TreeNode root = new TreeNode(nums[mid]);

        root.left = toBSTHelp(nums, start, mid-1);
        root.right= toBSTHelp(nums, mid+1, end);

        return root;