Given an integer, return its base 7 string representation. Example 1: Input: 100 Output: "202" Example 2: Input: -7 Output: "-10" Note: The input will be in range of [-1e7, 1e7]. 不停除以7, 然后把余数放到ans里面, 最后reverse ans加上符号即可. Code class Sol…

504. Base 7 Given an integer, return its base 7 string representation. Example 1: Input: 100 Output: "202" Example 2: Input: -7 Output: "-10" Note: The input will be in range of [-1e7, 1e7]. 思路:辗转相除法.…

Given an integer, return its base 7 string representation. Example 1: Input: 100 Output: "202" Example 2: Input: -7 Output: "-10"  Note: The input will be in range of [-1e7, 1e7]. 给一个整数,返回它的七进制数. 解法1: 迭代 解法2: 递归 Java: public class Solu…

Given a non-negative integer num, repeatedly add all its digits until the result has only one digit. Example: Input: 38 Output: 2 Explanation: The process is like: 3 + 8 = 11, 1 + 1 = 2.   Since 2 has only one digit, return it. Follow up:Could you do…

You have a total of n coins that you want to form in a staircase shape, where every k-th row must have exactly k coins. Given n, find the total number of full staircase rows that can be formed. n is a non-negative integer and fits within the range of…

题目: Given an integer, return its base 7 string representation. Example 1: Input: 100 Output: "202" Example 2: Input: -7 Output: "-10" Note: The input will be in range of [-1e7, 1e7]. 分析: 给定一个7进制数,求十进制表示,注意返回的是字符串. 进制转换没什么好说的,注意这道题测试用例是…

You are playing the following Nim Game with your friend: There is a heap of stones on the table, each time one of you take turns to remove 1 to 3 stones. The one who removes the last stone will be the winner. You will take the first turn to remove th…

There are 1000 buckets, one and only one of them contains poison, the rest are filled with water. They all look the same. If a pig drinks that poison it will die within 15 minutes. What is the minimum amount of pigs you need to figure out which bucke…

C#版 - Leetcode 504. 七进制数 - 题解 Leetcode 504. Base 7 在线提交: https://leetcode.com/problems/base-7/ 题目描述 给定一个整数,将其转化为7进制,并以字符串形式输出. 示例 1: 输入: 100 输出: "202" 示例 2: 输入: -7 输出: "-10" 注意: 输入范围是 [-1e7, 1e7] .   ●  题目难度: 简单 通过次数:707 提交次数:1.8K 贡献者:…

problem 504. Base 7 solution: class Solution { public: string convertToBase7(int num) { ) "; string ans = ""; int number = abs(num); ) { ans = to_string(number%) + ans; number /= ; } ) ans = "-" + ans; return ans; } }; 参考 1. Leetc…

Given a 2D board containing 'X' and 'O' (the letter O), capture all regions surrounded by 'X'. A region is captured by flipping all 'O's into 'X's in that surrounded region. Example: X X X X X O O X X X O X X O X X After running your function, the bo…

Given two non-negative integers num1 and num2 represented as string, return the sum of num1 and num2. Note: The length of both num1 and num2 is < 5100. Both num1 and num2 contains only digits 0-9. Both num1 and num2 does not contain any leading zero.…

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 内建库 BigInteger类 逐位计算 倍数相加 日期 题目地址:https://leetcode.com/problems/base-7/#/description 题目描述 Given an integer, return its base 7 string representation. Example 1: Input: 100 Outpu…

Given an integer, return its base 7 string representation. Example 1: Input: 100 Output: "202" Example 2: Input: -7 Output: "-10" Note: The input will be in range of [-1e7, 1e7]. class Solution(object): def convertToBase7(self, num): &…

For a web developer, it is very important to know how to design a web page's size. So, given a specific rectangular web page’s area, your job by now is to design a rectangular web page, whose length L and width W satisfy the following requirements: 1…

做个基本思路可以用 brute force, 但时间复杂度较高. 因为起始值都为0, 所以肯定是左上角的重合的最小的长方形就是结果, 所以我们求x, y 的最小值, 最后返回x*y. Code     T: O(m*n)    S: O(1) class Solution: def rangeAddition2(self, m, n, ops): for op1, op2 in ops: m = min(m, op1) n = min(n, op2) return m*n…

Given a positive integer num, write a function which returns True if num is a perfect square else False. Note: Do not use any built-in library function such as sqrt. Example 1: Input: 16 Returns: True Example 2: Input: 14 Returns: False Use Newton Me…

Given a positive integer, return its corresponding column title as appear in an Excel sheet. For example: 1 -> A 2 -> B 3 -> C ... 26 -> Z 27 -> AA 28 -> AB ... Example 1: Input: 1 Output: "A" Example 2: Input: 28 Output: "…

Given an integer n, return the number of trailing zeroes in n!. Example 1: Input: 3 Output: 0 Explanation: 3! = 6, no trailing zero. Example 2: Input: 5 Output: 1 Explanation: 5! = 120, one trailing zero. Note: Your solution should be in logarithmic…

A self-dividing number is a number that is divisible by every digit it contains. For example, 128 is a self-dividing number because 128 % 1 == 0, 128 % 2 == 0, and 128 % 8 == 0. Also, a self-dividing number is not allowed to contain the digit zero. G…

Given a collection of integers that might contain duplicates, nums, return all possible subsets (the power set). Note: The solution set must not contain duplicate subsets. Example: Input: [1,2,2] Output: [ [2], [1], [1,2,2], [2,2], [1,2], [] ] 这个题目思路…

Given an integer array nums, find the contiguous subarray (containing at least one number) which has the largest sum and return its sum. Example: Input: [-2,1,-3,4,-1,2,1,-5,4], Output: 6 Explanation: [4,-1,2,1] has the largest sum = 6. 这个题目思路跟[LeetC…

Given n balloons, indexed from 0 to n-1. Each balloon is painted with a number on it represented by array nums. You are asked to burst all the balloons. If the you burst balloon i you will get nums[left] * nums[i] * nums[right] coins. Here left and r…

Given two words word1 and word2, find the minimum number of operations required to convert word1to word2. You have the following 3 operations permitted on a word: Insert a character Delete a character Replace a character Example 1: Input: word1 = "ho…

原题链接在这里:https://leetcode.com/problems/add-bold-tag-in-string/description/ 题目: Given a string s and a list of strings dict, you need to add a closed pair of bold tag <b> and </b> to wrap the substrings in s that exist in dict. If two such subst…

LeetCode 七进制数 前言: 这个就没什么好说的了 题目:略 步入正题 进位制转换 10 -n 余数加倒叙 没什么好讲的直接上七进制代码 偷个懒 10进位制转7 class Solution { String ans = ""; public String convertToBase7(int num) { if(num == 0){ return "0"; } convertToBase7(num/7); ans+= Math.abs(num%7); ret…

Given a sorted (in ascending order) integer array nums of n elements and a target value, write a function to search target in nums. If target exists, then return its index, otherwise return -1. Example 1: Input: nums = [-1,0,3,5,9,12], target = 9 Out…

Given an integer, return its base 7 string representation. Example 1: Input: 100 Output: "202" Example 2: Input: -7 Output: "-10" Note: The input will be in range of [-1e7, 1e7]. 解题:题意很容易理解,将十进制整型数转化为七进制的数,并以字符串的形式返回.先看我写的第一种方法,比较繁琐,也利…

给定一个整数,将其转化为7进制,并以字符串形式输出.示例 1:输入: 100输出: "202" 示例 2:输入: -7输出: "-10"注意: 输入范围是 [-1e7, 1e7] .详见:https://leetcode.com/problems/base-7/description/ C++: class Solution { public: string convertToBase7(int num) { if(num==0) { return "0&…

一.204. Count Primes Count the number of prime numbers less than a non-negative number, n. Input: 10 Output: 4 Explanation: There are 4 prime numbers less than 10, they are 2, 3, 5, 7. 1.数学原理:两个质数的乘积一定是合数.一个质数乘以任何数的积都一定不是质数.(除了1) 2.代码:需要注意的点:for (int…