题目描述: Given an integer, convert it to a roman numeral. Input is guaranteed to be within the range from 1 to 3999. Subscribe to see which companies asked this question Show Tags Show Similar Problems 准备知识看上篇博客 leetcode之旅(10)-Roman to Integer 思路: 当前这个数…

题目介绍: Given two strings s and t, write a function to determine if t is an anagram of s. For example, s = "anagram", t = "nagaram", return true. s = "rat", t = "car", return false. Note: You may assume the string con…

LeetCode 287. Find the Duplicate Number 暴力解法 时间 O(nlog(n)),空间O(n),按题目中Note"只用O(1)的空间",照理是过不了的,但是可能判题并没有卡空间复杂度,所以也能AC. class Solution: # 基本思路为,将第一次出现的数字 def findDuplicate(self, nums: List[int]) -> int: s = set() for i in nums: a = i in s if a…

题目 Write an algorithm to determine if a number is "happy". A happy number is a number defined by the following process: Starting with any positive integer, replace the number by the sum of the squares of its digits, and repeat the process until…

题目: Write a program to check whether a given number is an ugly number. Ugly numbers are positive numbers whose prime factors only include 2, 3, 5. For example, 6, 8 are ugly while 14 is not ugly since it includes another prime factor 7. Note that 1 i…

题目描述: 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 the function shoul…

Given an array nums containing n + 1 integers where each integer is between 1 and n (inclusive), prove that at least one duplicate number must exist. Assume that there is only one duplicate number, find the duplicate one. Note: You must not modify th…

题目链接 题目要求: Given a list of non negative integers, arrange them such that they form the largest number. For example, given [3, 30, 34, 5, 9], the largest formed number is 9534330. Note: The result may be very large, so you need to return a string inst…

problem 414. Third Maximum Number solution 思路:用三个变量first, second, third来分别保存第一大.第二大和第三大的数,然后遍历数组. class Solution { public: int thirdMax(vector<int>& nums) { //1.LONG_MIN; long first = LONG_MIN, second = LONG_MIN, third = LONG_MIN;// for(auto a:n…

题目 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? 分析 由上一题改动而来,LeetCode 136 Single Nu…

Related to question Excel Sheet Column Title Given a column title as appear in an Excel sheet, return its corresponding column number. For example: A -> 1 B -> 2 C -> 3 ... Z -> 26 AA -> 27 AB -> 28 题目标签:Math 这一题和 #168 是逆向思维. 从string s 的…

题目:https://leetcode.com/problems/kth-smallest-number-in-multiplication-table/description/ 668. Kth Smallest Number in Multiplication Table Nearly every one have used the Multiplication Table. But could you find out the k-th smallest number quickly fr…

题目: 给定一个由 '1'(陆地)和 '0'(水)组成的的二维网格,计算岛屿的数量.一个岛被水包围,并且它是通过水平方向或垂直方向上相邻的陆地连接而成的.你可以假设网格的四个边均被水包围. Given a 2d grid map of '1's (land) and '0's (water), count the number of islands. An island is surrounded by water and is formed by connecting adjacent lan…

Given an array nums containing n + 1 integers where each integer is between 1 and n (inclusive), prove that at least one duplicate number must exist. Assume that there is only one duplicate number, find the duplicate one. Example 1: Input: [1,3,4,2,2…

原题链接在这里:https://leetcode.com/problems/check-if-a-number-is-majority-element-in-a-sorted-array/ 题目: Given an array nums sorted in non-decreasing order, and a number target, return True if and only if target is a majority element. A majority element is…

Related to question Excel Sheet Column Title Given a column title as appear in an Excel sheet, return its corresponding column number. For example: A -> 1 B -> 2 C -> 3 ... Z -> 26 AA -> 27 AB -> 28 Credits:Special thanks to @ts for addi…

在此记录一下用javascript刷leetcode的过程,每天都要坚持! 1.Two Sum Given an array of integers, find two numbers such that they add up to a specific target number. The function twoSum should return indices of the two numbers such that they add up to the target, where in…

9. Palindrome Number Determine whether an integer is a palindrome. Do this without extra space. click to show spoilers. Some hints: Could negative integers be palindromes? (ie, -1) If you are thinking of converting the integer to string, note the res…

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 桶排序 日期 题目地址:https://leetcode-cn.com/problems/check-if-a-number-is-majority-element-in-a-sorted-array/ 题目描述 Given an array of integers A`, return the largest integer that only oc…

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 Java解法 Python解法 日期 题目地址:https://leetcode.com/problems/convert-a-number-to-hexadecimal/ 题目描述 Given an integer, write an algorithm to convert it to hexadecimal. For negative inte…

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 数学 日期 题目地址:https://leetcode.com/problems/reach-a-number/description/ 题目描述 You are standing at position 0 on an infinite number line. There is a goal at position target. On each…

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 替换最大值数组 使用set 三个变量 日期 题目地址:https://leetcode.com/problems/third-maximum-number/description/ 题目描述 Given a non-empty array of integers, return the third maximum number in this arr…

作者: 负雪明烛 id: fuxuemingzhu 个人博客: http://fuxuemingzhu.cn/ 题目地址:https://leetcode.com/problems/valid-triangle-number/description/ 题目描述: Given an array consists of non-negative integers, your task is to count the number of triplets chosen from the array t…

Related to question Excel Sheet Column Title Given a column title as appear in an Excel sheet, return its corresponding column number. For example: A -> 1 B -> 2 C -> 3 ... Z -> 26 AA -> 27 AB -> 28 很简单. public class Solution { public in…

Problem: Given a column title as appear in an Excel sheet, return its corresponding column number. For example: A -> 1 B -> 2 C -> 3 ... Z -> 26 AA -> 27 AB -> 28 Summary: 将二十六进制数字转为十进制. Analysis: class Solution { public: int titleToNumb…

https://leetcode.com/problems/excel-sheet-column-number/ class Solution { public: int titleToNumber(string s) { int ans = 0; for(int i = 0;i < s.length();i++) { ans *= 26; ans += s[i] - 'A' + 1; } return ans; } };…

Excel Sheet Column Number Related to question Excel Sheet Column Title Given a column title as appear in an Excel sheet, return its corresponding column number. For example: A -> 1 B -> 2 C -> 3 ... Z -> 26 AA -> 27 AB -> 28   class Solu…

Related to question Excel Sheet Column Title Given a column title as appear in an Excel sheet, return its corresponding column number. For example: A -> 1    B -> 2    C -> 3    ...    Z -> 26    AA -> 27    AB -> 28 解题思路: JAVA实现如下: publ…

#-*- coding: UTF-8 -*-# The guess API is already defined for you.# @param num, your guess# @return -1 if my number is lower, 1 if my number is higher, otherwise return 0# def guess(num):#binary searchclass Solution(object):    def guessNumber(self, n…

Given a column title as appear in an Excel sheet, return its corresponding column number. For example: A -> 1 B -> 2 C -> 3 ... Z -> 26 AA -> 27 AB -> 28 这题题目的意思就是:将26进制字母转化为10进制数字 class Solution { public: int titleToNumber(string s) { i…