思路:先二分查找到一个和target相同的元素,然后再左边二分查找左边界,右边二分查找有边界. class Solution { public: , end = -; int ends; int lSearch(int left, int right, vector<int>& nums, int target) { ; ; if(nums[mid] == target){ || (mid > && nums[mid - ] < target)) retur…

本人编程小白,如果有写的不对.或者能更完善的地方请个位批评指正! 这个是leetcode的第34题,这道题的tag是数组,需要用到二分搜索法来解答 34. Find First and Last Position of Element in Sorted Array Given an array of integers nums sorted in ascending order, find the starting and ending position of a given target v…

一.题目说明 题目是34. Find First and Last Position of Element in Sorted Array,查找一个给定值的起止位置,时间复杂度要求是Olog(n).题目的难度是Medium! 二.我的解答 这个题目还是二分查找(折半查找),稍微变化一下.target==nums[mid]后,需要找前面.后面的值是否=target. 一次写出来,bug free,熟能生巧!怎一个爽字了得! #include<iostream> #include<vecto…

Given an array of integers nums sorted in ascending order, find the starting and ending position of a given target value. Your algorithm's runtime complexity must be in the order of O(log n). If the target is not found in the array, return [-1, -1].…

Given an array of integers nums sorted in ascending order, find the starting and ending position of a given target value. Your algorithm's runtime complexity must be in the order of O(log n). If the target is not found in the array, return [-1, -1].…

作者: 负雪明烛 id: fuxuemingzhu 个人博客: http://fuxuemingzhu.cn/ 目录 题目描述 题目大意 解题方法 二分查找 日期 题目地址:https://leetcode.com/problems/find-first-and-last-position-of-element-in-sorted-array/description/ 题目描述 Given an array of integers nums sorted in ascending order,…

Given an array of integers nums sorted in ascending order, find the starting and ending position of a given target value. Your algorithm's runtime complexity must be in the order of O(log n). If the target is not found in the array, return [-1, -1].…

Description Given a sorted array of n integers, find the starting and ending position of a given target value. If the target is not found in the array, return [-1, -1]. Example Given [5, 7, 7, 8, 8, 10] and target value 8,return [3, 4]. Challenge O(l…

Given an array of integers nums sorted in ascending order, find the starting and ending position of a given target value. Your algorithm's runtime complexity must be in the order of O(log n). If the target is not found in the array, return [-1, -1].…

题意懒得抄了,大概是:在升序数组中给定整数target,找到第一个和最后一个target的索引,找到返回{index1, index2},否则返回{-1, -1}: 时间复杂度要求:O(logn) 分析:要求对数时间,又是查找,我们不难想到二分查找.但是有一点,怎么查到第一个和最后一个呢?这困扰了我. 算法:来自leetcode caikehe 1. 使用二分变体,查找target作为index1,再找target+1, 作为index2: 2. 对index做判断,如果它未越界且它的对应值等于…