We define the Perfect Number is a positive integer that is equal to the sum of all its positive divisors except itself. Now, given an integer n, write a function that returns true when it is a perfect number and false when it is not. Example: Input:…

We define the Perfect Number is a positive integer that is equal to the sum of all its positive divisors except itself. Now, given an integer n, write a function that returns true when it is a perfect number and false when it is not. Example: Input:…

对于一个 正整数,如果它和除了它自身以外的所有正因子之和相等,我们称它为“完美数”.给定一个 正整数 n, 如果他是完美数,返回 True,否则返回 False示例:输入: 28输出: True解释: 28 = 1 + 2 + 4 + 7 + 14注意:输入的数字 n 不会超过 100,000,000. (1e8)详见:https://leetcode.com/problems/perfect-number/description/ C++: class Solution { public: b…

problem 507. Perfect Number solution: /* class Solution { public: bool checkPerfectNumber(int num) { int sum = 1; for(int i=2; i*i<=num; i++) { if(num%i==0) sum += i + (num/i == i) ? 0 : num/i; // } return (sum == num) && (num!=1); } }; */ clas…

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 日期 题目地址:https://leetcode.com/problems/perfect-number/#/description 题目描述 We define the Perfect Number is a positive integer that is equal to the sum of all its positive divisors…

We define the Perfect Number is a positive integer that is equal to the sum of all its positive divisors except itself. Now, given an integer n, write a function that returns true when it is a perfect number and false when it is not. Example: Input:…

［抄题］: We define the Perfect Number is a positive integer that is equal to the sum of all its positive divisors except itself. Now, given an integer n, write a function that returns true when it is a perfect number and false when it is not. Example: I…

Validate if a given string can be interpreted as a decimal number. Some examples:"0" => true" 0.1 " => true"abc" => false"1 a" => false"2e10" => true" -90e3   " => true" 1e…

题目: Given an array containing n distinct numbers taken from 0, 1, 2, ..., n, find the one that is missing from the array. Example 1: Input: [3,0,1] Output: 2 Example 2: Input: [9,6,4,2,3,5,7,0,1] Output: 8 Note:Your algorithm should run in linear run…

这是悦乐书的第249次更新,第262篇原创 01 看题和准备 今天介绍的是LeetCode算法题中Easy级别的第116题(顺位题号是507).我们定义Perfect Number是一个正整数,它等于除了它自己之外的所有正除数之和.现在,给定一个整数n,编写一个函数,当它是一个完美数字时返回true,否则返回false.例如: 输入:28 输出:true 说明:28 = 1 + 2 + 4 + 7 + 14 注意:输入数字n不会超过100,000,000.(1E8) 本次解题使用的开发工具是ec…

We define the Perfect Number is a positive integer that is equal to the sum of all its positive divisors except itself. Now, given an integer n, write a function that returns true when it is a perfect number and false when it is not. Example: Input:…

问题 该文章的最新版本已迁移至个人博客[比特飞],单击链接 https://www.byteflying.com/archives/3879 访问. 对于一个 正整数,如果它和除了它自身以外的所有正因子之和相等,我们称它为"完美数". 给定一个 正整数 n, 如果他是完美数,返回 True,否则返回 False 输入: 28 输出: True 解释: 28 = 1 + 2 + 4 + 7 + 14 注意:输入的数字 n 不会超过 100,000,000. (1e8) We define…

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…

LeetCode 260. Single Number III(只出现一次的数字 III)…

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

LeetCode 136. Single Number(只出现一次的数字)…

翻译 给定一个整型数组,除了某个元素外其余的均出现了三次. 找出这个元素. 备注: 你的算法应该是线性时间复杂度. 你能够不用额外的空间来实现它吗? 原文 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…

原题链接在这里:https://leetcode.com/problems/perfect-number/#/description 题目: We define the Perfect Number is a positive integer that is equal to the sum of all its positive divisors except itself. Now, given an integer n, write a function that returns true…

翻译 给定一个整型数组,除了某个元素外其余元素均出现两次. 找出这个仅仅出现一次的元素. 备注: 你的算法应该是一个线性时间复杂度. 你能够不用额外空间来实现它吗? 原文 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 yo…

We are playing the Guess Game. The game is as follows: I pick a number from 1 to n. You have to guess which number I picked. Every time you guess wrong, I'll tell you whether the number I picked is higher or lower. However, when you guess a particula…

A strobogrammatic number is a number that looks the same when rotated 180 degrees (looked at upside down). Write a function to determine if a number is strobogrammatic. The number is represented as a string. For example, the numbers "69", "…

A strobogrammatic number is a number that looks the same when rotated 180 degrees (looked at upside down). Find all strobogrammatic numbers that are of length = n. For example,Given n = 2, return ["11","69","88","96"…

LeetCode 279. Perfect Squres DP 是笨办法中的高效办法,又是一道可以被好办法打败的 DP 题. 题目描述 Given a positive integer n, find the least number of perfect square numbers (for example, 1, 4, 9, 16, ...) which sum to n. Example 1: Input: n = 12 Output: 3 Explanation: 12 = 4 + 4…

[LeetCode]Largest Number 解题报告 标签(空格分隔): LeetCode 题目地址:https://leetcode.com/problems/largest-number/#/description 题目描述: Given a list of non negative integers, arrange them such that they form the largest number. For example, given [3, 30, 34, 5, 9], t…

今天先谈下弗洛伊德判环,弗洛伊德判环原来是在一个圈内有两人跑步,同时起跑,一人的速度是另一人的两倍,则那个人能在下一圈追上另一个人,弗洛伊德判环能解数字会循环出现的题,比如说判断一个链表是不是循环链表.在程序中具体表现为 one = change(one); //一倍速度 two = change(change(two));//两倍速度 即一倍速度的人调用生成函数change一次,两倍速度的人调用生成函数change两次. Leetcode 202 Happy Number 就是这样一道简单的题…

---Number类型的细节,其包含的基本数字类型 ---Number基本数字类型之间的数值转换 ---Number上面的数学函数,有些可以直接调用,有些需要导入库 参见http://www.runoob.com/python/python-numbers.html 扩充下面的笔记…

 题目链接:https://nanti.jisuanke.com/t/38220 题目大意:这道题让我们判断给定数字是否为完美数字,并给来完美数字的定义,就是一个整数等于除其自身之外的所有的因子之和. 首先打表前三个,发现满足 n = 1+2^1 + 2^2 + 2^3 + 2^z + (n/(2^1))+(n/(2^2))+...+n/(2^z). 然后化简这个式子,就是n=2^z*(2^z-1).然后枚举z就可以了,看看有没有满足的. AC代码: #include<bits/stdc++.h…

leetcode 136. 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? 解题思路: 如果以线性复杂度和…

题目 Determine whether an integer is a palindrome. Do this without extra space. Some hints: Could negative integers be palindromes? (ie, -1) If you are thinking of converting the integer to string, note the restriction of using extra space. You could a…

LeetCode:至少是其他数字两倍的最大数[747] 题目描述 在一个给定的数组nums中,总是存在一个最大元素 . 查找数组中的最大元素是否至少是数组中每个其他数字的两倍. 如果是,则返回最大元素的索引,否则返回-1. 示例 1: 输入: nums = [3, 6, 1, 0] 输出: 1 解释: 6是最大的整数, 对于数组中的其他整数, 6大于数组中其他元素的两倍.6的索引是1, 所以我们返回1. 示例 2: 输入: nums = [1, 2, 3, 4] 输出: -1 解释: 4没有超过…