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…

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…

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…

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: 在 Single Number I 中使用了异或一个数两次,原值…

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? 自己不会做... 搜答案,发现思路真是太巧妙了 关键:统计每一位上出现1的次…

int singleNumber(int A[], int n) { int once = 0; int twice = 0; int three = 0; for (int i = 0; i < n; ++i) { //在计算新的once 前,计算twice twice |= once & A[i]; //计算新的once once ^= A[i]; three = ~(once & twice); //将3次的1都清理掉 once &= three; twice &…

Single Number I : 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? Solution: 解法不少,贴一种: class…

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…

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…

感谢:http://www.cnblogs.com/changchengxiao/p/3413294.html Single Number Total Accepted: 103007 Total Submissions: 217483 Difficulty: Medium Given an array of integers, every element appears twice except for one. Find that single one. Note:Your algorith…