LeetCode 108. Convert Sorted Array to Binary Search Tree

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已排序数组建二叉搜索树

根据性质建树即可

/** * 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) {        if (nums.length == 0) return null;        int len = nums.length;        int mid = len / 2;        TreeNode root = new TreeNode(nums[mid]);        root.left = buildSubTree(0, mid, nums);        root.right = buildSubTree(mid + 1, len, nums);        return root;    }        private static TreeNode buildSubTree(int sta, int end, int[] nums) {        if (sta == end) { return null; }        int mid = (sta + end) / 2;        TreeNode root = new TreeNode(nums[mid]);        root.left = buildSubTree(sta, mid, nums);        root.right = buildSubTree(mid + 1, end, nums);        return root;    }}

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