题目 丢失的第一个正整数 给出一个无序的整数数组,找出其中没有出现的最小正整数. 样例 如果给出 [1,2,0], return 3 如果给出 [3,4,-1,1], return 2 挑战 只允许时间复杂度O(n)的算法,并且只能使用常数级别的空间. 解题  感觉好像好像很复杂,通过率21%也是比较低的了. 找了一个很不好的方法 步骤: 1.先找出数组中正整数的最小值,Min 2.若Min>1 显然最小的不在数组中的正整数就是1 3.这里的都是最小值Min == 1的情况 对于这个情况,只需要…

Given an unsorted integer array, find the smallest missing positive integer. Example 1: Input: [1,2,0]Output: 3Example 2: Input: [3,4,-1,1]Output: 2Example 3: Input: [7,8,9,11,12]Output: 1Note: Your algorithm should run in O(n) time and uses constant…

First Missing Positive  Given an unsorted integer array, find the first missing positive integer. For example, Given [1,2,0] return 3, and [3,4,-1,1] return 2. Your algorithm should run in O(n) time and uses constant space. 思路:这个题刚開始是没有思路的,难就难在O(n)时间…

在leetCode上做的第一个难度是hard的题,题目如下: Given an unsorted integer array, find the first missing positive integer. For example,Given [1,2,0] return 3,and [3,4,-1,1] return 2. Your algorithm should run in O(n) time and uses constant space. 关键是要实现0(N)的时间复杂度以及常数级…

Given an unsorted integer array, find the smallest missing positive integer. Example 1: Input: [1,2,0] Output: 3 Example 2: Input: [3,4,-1,1] Output: 2 Example 3: Input: [7,8,9,11,12] Output: 1 Note: Your algorithm should run in O(n) time and uses co…

Given an unsorted integer array, find the smallest missing positive integer. Example 1: Input: [1,2,0] Output: 3 Example 2: Input: [3,4,-1,1] Output: 2 Example 3: Input: [7,8,9,11,12] Output: 1 Note: Your algorithm should run in O(n) time and uses co…

41. First Missing Positive Given an unsorted integer array, find the first missing positive integer. For example, Given [1,2,0] return 3, and [3,4,-1,1] return 2. Your algorithm should run in O(n) time and uses constant space. My Thought 题目大意 给定一个数组,…

题目 Given an unsorted integer array, find the first missing positive integer. For example, Given [1,2,0] return 3, and [3,4,-1,1] return 2. Your algorithm should run in O(n) time and uses constant space. 分析 题目给定一个无序序列,要求返回第一个丢失的正整数. 限制时间复杂度为O(n),空间消耗为…

Given an unsorted integer array, find the first missing positive integer. For example,Given [1,2,0] return 3,and [3,4,-1,1] return 2. Your algorithm should run in O(n) time and uses constant space. 这道题让我们找缺失的首个正数,由于限定了O(n)的时间,所以一般的排序方法都不能用,最开始我没有看到还限…

Given an unsorted integer array, find the first missing positive integer. For example,Given [1,2,0] return 3,and [3,4,-1,1] return 2. Your algorithm should run in O(n) time and uses constant space. 给定无序整型数组,找出第一个不在数组里的正整数,要求时间复杂度为O(n),空间复杂度为O(1) 本题使用…

First Missing Positive Given an unsorted integer array, find the first missing positive integer. For example,Given [1,2,0] return 3,and [3,4,-1,1] return 2. Your algorithm should run in O(n) time and uses constant space. 通过swap操作,把各个元素swap到相应的位置上,然后再…

Given an unsorted integer array, find the first missing positive integer. For example,Given [1,2,0] return 3,and [3,4,-1,1] return 2. Your algorithm should run in O(n) time and uses constant space. 思路: 又是一个不让排序,但是要得到跟排序有关信息的.想了半天,只能空间换时间,可是又只能用常量空间,这…

41. First Missing Positive Problem's Link ---------------------------------------------------------------------------- Mean: 给你一组整数,找出第一个空缺的正整数. 要求:时间O(n),空间O(n). analyse: 这题时间O(n)想了半天没想到,用O(n*logn)过的. 然后看了discuss,想法非常巧妙,自愧不如. Time complexity: O(N) v…

Given an unsorted integer array, find the first missing positive integer. For example,Given [1,2,0] return 3,and [3,4,-1,1] return 2. Your algorithm should run in O(n) time and uses constant space. 分析: 因为数组的大小为n,因此那个缺失的整数只可能的范围[1,n+1] 方法一:需要O(n)的空间,设…

Given an unsorted integer array, find the first missing positive integer. For example,Given [1,2,0] return 3,and [3,4,-1,1] return 2. Your algorithm should run in O(n) time and uses constant space. 这道题求的是在一个乱序数组中缺少的第一个正数,要求时间复杂度o(n)空间复杂度为1. 先上代码 pack…

题目: Given an unsorted integer array, find the first missing positive integer. For example,Given [1,2,0] return 3,and [3,4,-1,1] return 2. Your algorithm should run in O(n) time and uses constant space.(Hard) 分析: 如果题目要求是O(n^2)时间复杂度,O(1)空间复杂度,或O(n)时间复杂…

题目描述: Given an unsorted integer array, find the first missing positive integer. For example,Given [1,2,0] return 3,and [3,4,-1,1] return 2. Your algorithm should run in O(n) time and uses constant space. 解题思路: 参考http://blog.csdn.net/nanjunxiao/articl…

Given an unsorted integer array, find the first missing positive integer. For example,Given [1,2,0] return 3,and [3,4,-1,1] return 2. Your algorithm should run in O(n) time and uses constant space. 题意: 给定了一个无序数组,要求找到第一个缺失的正整数.如1,2,4,5的第一个缺失的正整数是3.要求时…

# -*- coding: utf8 -*-'''__author__ = 'dabay.wang@gmail.com' 41: First Missing Positivehttps://oj.leetcode.com/problems/first-missing-positive/ Given an unsorted integer array, find the first missing positive integer.For example,Given [1,2,0] return…

First Missing Positive Given an unsorted integer array, find the first missing positive integer. For example,Given [1,2,0] return 3,and [3,4,-1,1] return 2. Your algorithm should run in O(n) time and uses constant space. 题目意思: 返回第一个缺失的正数. 时间复杂度应该在O(n…

268. Missing Number Given an array containing n distinct numbers taken from 0, 1, 2, ..., n, find the one that is missing from the array. For example,Given nums = [0, 1, 3] return 2. Note:Your algorithm should run in linear runtime complexity. Could…

Given an unsorted integer array, find the first missing positive integer. For example,Given [1,2,0] return 3,and [3,4,-1,1] return 2. Your algorithm should run in O(n) time and uses constant space. 题意分析: 本题是给一个整数的数组,让你按顺序找出第一个缺失的正整数.也就是说从1开始查找,找到了1再找…

题目: Given an unsorted integer array, find the first missing positive integer. For example,Given [1,2,0] return 3,and [3,4,-1,1] return 2. Your algorithm should run in O(n) time and uses constant space. 给定一个没有排好序的数组.找出其中第一个消逝的正整数.例如 [1,2,5,4]那就是缺3. 思路…

Given an unsorted integer array, find the first missing positive integer. For example,Given [1,2,0] return 3,and [3,4,-1,1] return 2. Your algorithm should run in O(n) time and uses constant space. [题目分析] 给定一个整数数组,找出数组中第一个缺失的正整数.比如[1,2,0]缺少3,[3,4,-1,…

leetcode - 41. First Missing Positive - Hard descrition Given an unsorted integer array, find the first missing positive integer. For example, Given [1,2,0] return 3, and [3,4,-1,1] return 2. Your algorithm should run in O(n) time and uses constant s…

Given an unsorted integer array, find the first missing positive integer. For example, Given [1,2,0] return 3, and [3,4,-1,1] return 2. Your algorithm should run in \(O(n)\) time and uses constant space. 若数组为[10,20,30], 则返回0+1 = 1, 因为 A[0]!=( 0 + 1 )…

一天一道LeetCode系列 (一)题目 Given an unsorted integer array, find the first missing positive integer. For example, Given [1,2,0] return 3, and [3,4,-1,1] return 2. Your algorithm should run in O(n) time and uses constant space. (二)解题 /* 首先对初始vector进行排序,然后设定…

Given an unsorted integer array, find the smallest missing positive integer. Example 1: Input: [1,2,0] Output: 3 Example 2: Input: [3,4,-1,1] Output: 2 Example 3: Input: [7,8,9,11,12] Output: 1 Note: Your algorithm should run in O(n) time and uses co…

Given an unsorted integer array, find the first missing positive integer. For example,Given [1,2,0] return 3,and [3,4,-1,1] return 2. Your algorithm should run in O(n) time and uses constant space. 给出一组数,找到里面缺少的第一个正数. 让o(n)时间,而且是o(1)空间. 一开始想的是记录正数的个数…

Given an unsorted integer array, find the first missing positive integer. For example,Given [1,2,0] return 3,and [3,4,-1,1] return 2. Your algorithm should run in O(n) time and uses constant space. 题目: 给一无序数组,找到数组中从1开始第一个不出现的正整数. 要求O(n)的时间复杂度和常数空间复杂度…