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? 题意:一个整数数组中,除了一个数以外的其他数字都出现了两次…

题目来源: https://leetcode.com/problems/single-number-ii/ 题意分析: 给定一个数组,数组里面每一个数字都出现了3次除了一个,找出那个数.要求时间复杂度O(n),空间复杂度O(1). 题目思路: 把所有的数转化成32位的2进制.那么如果没有只出现一次的那个数,每个位的1的个数都是3的倍数,那么我们将所有位置上的数量都对3取余数,那么剩下的就是那个数的32位组成. 代码(python): class Solution(object): def sin…

题目来源: https://leetcode.com/problems/single-number/ 题意分析: 给定一个数组,每个数都出现了2次,只有一个出现了一次,找出这个数.要求时间复杂度O(n),空间复杂度O(1). 题目思路: 这道题目利用位操作.位操作的异或(^),他的其中一个属性是,n^n = 0, 0^n = n.只要将所有的数都进行异或就得到出现一次的数. 代码(python): class Solution(object): def singleNumber(self, nu…

今天做了三道LeetCode上的简单题目,每道题都是用c++和Python两种语言写的.由于c++版的代码网上比較多.所以就仅仅分享一下Python的代码吧,刚学完Python的基本的语法,做做LeetCode的题目还是不错的,对以后找工作面试也有帮助! 刚開始就从AC率最高的入手吧! 1.Given an array of integers, every element appears twice except for one. Find that single one. Note: Your…

Python 位操作: 按位与 &, 按位或 | 体会不到 按位异或 ^ num ^ num = 0 左移 << num << 1 == num * 2**1 右移 >> num >> 2 == num / 2**2 取反 ~ ~num == -(num + 1) 1. Single Number Given an array of integers, every element appears twice except for one. Find…

一. 基础数字操作 1.加减乘除以及内置函数: min(),  max(),  sum(),  abs(),  len()         math库: math.pi math.e, math.sin math.sqrt math.pow() # -*- coding:UTF-8 -*-import math, random a, b = 1, 100 # 整形 integer result = [] for i in range(20): number = random.randint( a…

LeetCode初级算法的Python实现--数组 # -*- coding: utf-8 -*- """ @Created on 2018/6/3 17:06 @author: ZhifengFang """ # 排列数组删除重复项 def removeDuplicates(nums): if len(nums) <= 1: return len(nums) i = 1 while len(nums) != i: if nums[i] =…

1. Two Sum Given an array of integers, return indices of the two numbers such that they add up to a specific target. You may assume that each input would have exactly one solution, and you may not use the same element twice. Example: Given nums = [2,…

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 异或 字典 日期 [LeetCode] 题目地址:https://leetcode.com/problems/single-number/ Total Accepted: 183838 Total Submissions: 348610 Difficulty: Easy 题目描述 Given a non-empty array of integers…

[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…