LeetCode : Search Insert Position [java]

二分查找算法实现元素插入位置

最新推荐文章于 2025-04-21 22:09:55 发布

原创最新推荐文章于 2025-04-21 22:09:55 发布 · 360 阅读

0 ·

CC 4.0 BY-SA版权

文章标签：

#LeetCode #Search Insert Positi

Java 同时被 2 个专栏收录

64 篇文章

订阅专栏

编程练习题

45 篇文章

订阅专栏

本文介绍如何使用二分查找算法确定已排序数组中目标值的位置或其应插入的位置，确保数组保持有序。通过实例演示算法实现，包括边界条件处理及返回插入位置。

Given a sorted array and a target value, return the index if the target is found. If not, return the index where it would be if it were inserted in order.

You may assume no duplicates in the array.

Here are few examples.
[1,3,5,6], 5 → 2
[1,3,5,6], 2 → 1
[1,3,5,6], 7 → 4

[1,3,5,6], 0 → 0

思路：二分查找。

public class Solution {
    public int searchInsert(int[] nums, int target) {
		int left = 0;
		int right = nums.length - 1;
		int inserIndex = -1;
		while (left <= right) {
			int mid = (left + right) / 2;
			if (nums[mid] == target) {
				return mid;
			} else if (nums[mid] > target) {
				right = mid - 1;
				inserIndex = mid;
			} else {
				left = mid + 1;
				inserIndex = left;
			}
		}
		return inserIndex;
    }
}