原题目 Given a non-empty 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? 普通解 刚看到的这个题目第一时间想到的就是a[i]++,最后…

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)…

Catenyms Time Limit: 1000MS   Memory Limit: 65536K Total Submissions: 8756   Accepted: 2306 Description A catenym is a pair of words separated by a period such that the last letter of the first word is the same as the last letter of the second. For e…

题目可以转化成求关于t的同余方程的最小非负数解: x+m*t≡y+n*t (mod L) 该方程又可以转化成: k*L+(n-m)*t=x-y 利用扩展欧几里得可以解决这个问题: eg:对于方程ax+by=c 设tm=gcd(a,b) 若c%tm!=0,则该方程无整数解. 否则,列出方程: a*x0+b*y0=tm 易用extend_gcd求出x0和y0 然后最终的解就是x=x0*(c/tm),y=y0*(c/tm) 注意:若是要求最小非负整数解? 例如求y的最小非负整数解, 令r=a/tm,则…

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? 本来是一道非常简单的题,但是由于加上了时间复杂度必须是O(n),并且空间复杂度为O(1)…

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? 这道题是之前那道 Single Number 单独的数字的延伸,那道题的解法…

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…

一:Number of 1 Bits 题目: Write a function that takes an unsigned integer and returns the number of '1' bits it has (also known as the Hamming weight). For example, the 32-bit integer '11' has binary representation 00000000000000000000000000001011, so t…

Problem 1:一个数组中有一个数字a只出现一次,其他数字都出现了两次.请找出这个只出现一次的数字? 考察知识点:异或运算 思路:比如数字 b^b = 0     a^0 = a 因此,可以将数组中的所有数字进行异或,而最终异或的结果即为所求只出现一次的数字a. 代码: def SingleNumber1(Array): ret = 0 for i in Array: ret ^= i return ret ==========================================…