一篇解析比较详细的文章:http://www.acmerblog.com/leetcode-single-number-ii-5394.html C++ 解法(1) 求出每个比特位的数目,然后%3,如果这个比特位只出现1次,那么这比特位就会余1,否则就会整除. 把每个余下的比特位求出来,就知道是哪个数只出现1次了. class Solution { public: /** * @param A : An integer array * @return : An integer */ int si…

Single Number II Given 3*n + 1 numbers, every numbers occurs triple times except one, find it. Example Given [1,1,2,3,3,3,2,2,4,1] return 4 Challenge One-pass, constant extra space. 统计每一位上的1出现的次数,然后模3 , 题目上的3 * n + 1给了提示,然后又做过一题2 * n + 1的位操作. public…

LintCode 83. Single Number II (Medium) LeetCode 137. Single Number II (Medium) 以下算法的复杂度都是: 时间复杂度: O(n) 空间复杂度: O(1) 解法1. 32个计数器 最简单的思路是用32个计数器, 满3复位0. class Solution { public: int singleNumberII(vector<int> &A) { int cnt[32] = {0}; int res = 0; f…

题目描述: Single Number Given an array of integers, every element appears twice except for one. Find that single one. Note: Your algorithm should have a linear runtime complexity. Could you implement it without using extra memory? Single Number II Given…

Given an array of integers, every element appears three times except for one. Find that single one. Note:Your algorithm should have a linear runtime complexity. Could you implement it without using extra memory? 思路: 这个题是Single Number的进阶版,如果其他的数都出现两次而…

Single Number Total Accepted: 103745 Total Submissions: 218647 Difficulty: Medium Given an array of integers, every element appears twice except for one. Find that single one. Note:Your algorithm should have a linear runtime complexity. Could you imp…

问题来源:Single Number II 问题描述:给定一个整数数组,除了一个整数出现一次之外,其余的每一个整数均出现三次,请找出这个出现一次的整数. 大家可能很熟悉另一个题目(Single Number):除了一个数出现一次之外,其余的均出现两次,找到出现一次的数.该问题很简单,大家肯定都知道解法:将所有的数异或,最后的结果即是出现一次的数.用到的知识是A^A=0,两个相同的数异或变为0,然后0^B=B,这样即可找到出现一次的数. 新问题有了变化,出现两次变成出现三次,整个问题的解法就不一样…

题目描述: 给定一个数组,里面除了一个数字,其他的都出现三次.求出这个数字 原文描述: Given an array of integers, every element appears three times except for one. Find that single one. Note: Your algorithm should have a linear runtime complexity. Could you implement it without using extra m…

136. Single Number 除了一个数字,其他数字都出现了两遍. 用亦或解决,亦或的特点:1.相同的数结果为0,不同的数结果为1 2.与自己亦或为0,与0亦或为原来的数 class Solution { public: int singleNumber(vector<int>& nums) { if(nums.empty()) ; ; ;i < nums.size();i++) res ^= nums[i]; return res; } }; 137. Single N…

原题地址https://leetcode.com/problems/single-number-ii/ 题目描述Given an array of integers, every element appears three times except for one. Find that single one. 给出一个整数数组,除了某个元素外所有元素都出现三次.找出仅出现一次的数字. Note: 注意: Your algorithm should have a linear runtime co…

Single Number II Given an array of integers, every element appears threetimes except for one. Find that single one. Note:Your algorithm should have a linear runtime complexity. Could you implement it without using extra memory? 解法一:开辟map记录次数 class So…

LeetCode 137. Single Number II(只出现一次的数字 II)…

1. Sum Root to Leaf Numbers Given a binary tree containing digits from 0-9 only, each root-to-leaf path could represent a number. An example is the root-to-leaf path 1->2->3 which represents the number 123. Find the total sum of all root-to-leaf num…

题目 Given an array of integers, every element appears three times except for one. Find that single one. Note: Your algorithm should have a linear runtime complexity. Could you implement it without using extra memory? 分析 由上一题改动而来,LeetCode 136 Single Nu…

136. Single Number Given an array of integers, every element appears twice except for one. Find that single one. (Easy) Note:Your algorithm should have a linear runtime complexity. Could you implement it without using extra memory? 分析: 第一问属于技巧题,做过就会,…

[LeetCode]137. Single Number II 解题报告(Python) 标签: LeetCode 题目地址:https://leetcode.com/problems/single-number-ii/description/ 题目描述: Given an array of integers, every element appears three times except for one, which appears exactly once. Find that singl…

问题: Given an array of integers, every element appears three times except for one. Find that single one. Note: Your algorithm should have a linear runtime complexity. Could you implement it without using extra memory?   Single Number I 升级版,一个数组中其它数出现了…

Majority Number II 原题链接: http://lintcode.com/en/problem/majority-number-ii/# Given an array of integers, the majority number is the number that occurs more than 1/3 of the size of the array. Find it. Note There is only one majority number in the arra…

Given an array of integers, every element appears three times except for one. Find that single one. Note:Your algorithm should have a linear runtime complexity. Could you implement it without using extra memory? 这道题是之前那道 Single Number 单独的数字的延伸,那道题的解法…

Given 2*n + 1 numbers, every numbers occurs twice except one, find it. Have you met this question in a real interview? Yes Example Given [1,2,2,1,3,4,3], return 4 Challenge One-pass, constant extra space. LeetCode上的原题,请参见我之前的博客Single Number. class So…

题目: Given an array of integers, every element appears three times except for one. Find that single one. Your algorithm should have a linear runtime complexity. Could you implement it without using extra memory?…

题目地址:here 题目大意:一个整数数组中,只有一个数出现一次,其余数都出现3次,在O(n)时间,O(1)空间内找到这个出现一次的数 对于”只有一个数出现一次,其余数出现2次“的情况,很简单,只要把数组中所有数异或的结果就是这个出现一次的数,leetcode上也有这个题目. 关于本题:我们用一个大小为32的数组cnt来记录:(int数据的每个二进制位1的出现次数)%3,程序中cnt[i]记录第i+1个二进制位.如果某个数出现了三次并且他的第i个二进制位为1,因为做了模3操作,那么该数对数组cn…

Given an array of integers, every element appears three times except for one. Find that single one. Note:Your algorithm should have a linear runtime complexity. Could you implement it without using extra memory? 没辙,智商碾压题.楼主没遇到之前就只会这种做法. public int si…

Problem link: http://oj.leetcode.com/problems/single-number-ii/ The problem seems like the Single Number. Suppose we have following (3m+1) numbers in the array A: x0, x1, x1, x1, ..., xm, xm, xm We are asked to find out the value of x0. However we ca…

Problem Discription: Suppose the array A has n items in which all of the numbers apear 3 times except one. Find the single number. int singleNumber2(int A[], int n) { ; while(n--) { ret ^= A[n]; } return ret; } Related Problem: Suppose the array A ha…

问题描述: Given an array of integers, every element appears three times except for one. Find that single one. Note:Your algorithm should have a linear runtime complexity. Could you implement it without using extra memory? 提示:bit manipulation(位操作) 参考:http…

C++ (1)异或操作 3^3=0 (2)for (auto &i : Obejuct) {} class Solution { public: /** * @param A: Array of integers. * return: The single number. */ int singleNumber(vector<int> &A) { // write your code here ; for (auto &i : A) { ret ^= i; } retu…

题目: Given an array of integers, every element appears three times except for one. Find that single one. Note: Your algorithm should have a linear runtime complexity. Could you implement it without using extra memory? 解题思路: 这题比Single Number稍难些,不能用异或解决…

原题地址:http://oj.leetcode.com/problems/single-number-ii/ 题意:Given an array of integers, every element appears three times except for one. Find that single one. 要求:和single number一样,线性时间复杂度,不能使用额外空间. 解题思路:这道题就比较难了.也是考察位操作.网上的位操作解法看了好半天也没有得其精髓.由于序列中除了那唯一的…

Given an array of integers, every element appears three times except for one, which appears exactly once. Find that single one. 题意: 在一个整型数组里,只有一个数字出现一次,其他数字都出现了3次,求这个只出现一次的数字(single number). 这真是非常非常有意思的一道题目.如果直接统计各数字出现的次数当然也能达到目的,不过空间复杂度为O(N).能否用O(1)…