博客
关于我
LeetCode.581 Shortest Unsorted Continuous Subarray
阅读量:806 次
发布时间:2019-03-17

本文共 2372 字,大约阅读时间需要 7 分钟。

To solve this problem, we need to find the shortest continuous subarray such that sorting this subarray in ascending order would make the entire array sorted in ascending order as well.

Approach

The approach to solve this problem involves the following steps:

  • Sort the Array: First, we create a sorted version of the input array. This helps us identify the segments of the array that are out of order.

  • Identify Differences: We compare the original array with the sorted array to find the indices where they first differ (start of the unsorted segment) and where they last differ (end of the unsorted segment).

  • Determine the Subarray Length: The length of the shortest subarray that needs to be sorted is given by the range from the first differing index to the last differing index, inclusive.

  • Solution Code

    public class Solution {    public int findMinimumSubarrayLength(int[] nums) {        int n = nums.length;        int[] sorted = Arrays.copyOf(nums, n);        Arrays.sort(sorted);                int start = 0;        while (start < n && sorted[start] == nums[start]) {            start++;        }                if (start >= n) {            return 0;        }                int end = n - 1;        while (end >= 0 && sorted[end] == nums[end]) {            end--;        }                return end - start + 1;    }}

    Explanation

  • Sorting the Array: We create a sorted version of the input array to compare against the original array and identify the unsorted segments.

  • Finding the Start of the Subarray: By iterating through the original array, we find the first index where the value does not match the corresponding value in the sorted array. This index marks the beginning of the segment that needs to be sorted.

  • Finding the End of the Subarray: Similarly, by iterating from the end of the array, we find the last index where the value does not match the corresponding value in the sorted array. This index marks the end of the segment that needs to be sorted.

  • Calculating the Length: The length of the subarray is calculated as the difference between the end and start indices, plus one.

  • This approach ensures that we efficiently find the shortest subarray that, when sorted, will result in the entire array being sorted. The time complexity is dominated by the sorting step, making it (O(n \log n)), which is efficient for large arrays up to 10,000 elements.

    转载地址:http://ekjez.baihongyu.com/

    你可能感兴趣的文章
    Python 安装避坑指南:从入门到进阶
    查看>>
    Python 安装配置详解
    查看>>
    Python 常见的错误类型和继承关系
    查看>>
    python 常量_零基础学Python系列之一:Python的变量与常量
    查看>>
    Python 并发编程
    查看>>
    python 微信扫码登录_python实现微信第三方网站扫码登录(Django)
    查看>>
    Python 快速下载依赖
    查看>>
    Python 接口并发测试详解
    查看>>
    Python 接口自动化 —— requests框架
    查看>>
    Python 无法安装包
    查看>>
    python 日历小部件 - 返回用户选择的日期
    查看>>
    Python 日志管理封装
    查看>>
    Python 是否优化尾递归?
    查看>>
    Python 更新set
    查看>>
    Python 最强 IDE 详细使用指南!
    查看>>
    Python 机器学习入门之 pandas 的使用
    查看>>
    Python处理Excel数据
    查看>>
    Python基础:集合与文件操作
    查看>>
    Python基础:搭建开发环境(1)
    查看>>
    PYTHON基础:如何阅读N个整数,直到#39;
    查看>>