방구석 개발자의 실험실

[해커랭크] Jumping on the Clouds

[해커랭크] Jumping on the Clouds https://www.hackerrank.com/challenges/jumping-on-the-clouds/problem?isFullScreen=true Jumping on the Clouds | HackerRankJumping on the cloudswww.hackerrank.com There is a new mobile game that starts with consecutively numbered clouds. Some of the clouds are thunderheads and others are cumulus. The player can jump on any cumulus cloud having a number that is equal to ..

[해커랭크] Repeated String

[해커랭크] Repeated Stringhttps://www.hackerrank.com/challenges/repeated-string/problem?isFullScreen=true Repeated String | HackerRankFind and print the number of letter a's in the first n letters of an infinitely large periodic string.www.hackerrank.com There is a string, , of lowercase English letters that is repeated infinitely many times. Given an integer, , find and print the number of letter..

[해커랭크] Non-Divisible Subset

[해커랭크] Non-Divisible Subset https://www.hackerrank.com/challenges/non-divisible-subset/problem?isFullScreen=true Non-Divisible Subset | HackerRankFind the size of the maximal non-divisible subset.www.hackerrank.com Given a set of distinct integers, print the size of a maximal subset of where the sum of any numbers in is not evenly divisible by .서로 다른 정수 집합이 주어졌을 때, 의 최대 부분집합의 크기를 출력하는데, 여기서 임..

작동하는 네트워크 계층과 처리하는 트래픽의 종류 가 다름. NLB (Network Load Balancer)계층: 네트워크 계층(L4)트래픽: TCP, UDP주요 특징:IP 주소와 포트 번호만으로 트래픽을 분산하므로 매우 빠르고 지연 시간이 낮습니다.정적(고정) IP 주소를 사용할 수 있습니다.SSL/TLS 종료는 애플리케이션 단에서 직접 처리해야 합니다.대규모 트래픽 처리에 적합하며, 복잡한 라우팅 기능이 필요 없을 때 유리합니다. ALB (Application Load Balancer)계층: 애플리케이션 계층(L7)트래픽: HTTP, HTTPS주요 특징:HTTP/HTTPS 헤더를 보고 트래픽을 세밀하게 제어할 수 있습니다.URL 경로, 호스트 이름 등을 기반으로 트래픽을 다양한 대상 그룹으로 라우..

[해커랭크] Cut the sticks https://www.hackerrank.com/challenges/cut-the-sticks/problem?isFullScreen=true Cut the sticks | HackerRankGiven the lengths of n sticks, print the number of sticks that are left before each cut operation.www.hackerrank.com You are given a number of sticks of varying lengths. You will iteratively cut the sticks into smaller sticks, discarding the shortest pieces until there ..

[해커랭크] Library Fine https://www.hackerrank.com/challenges/library-fine/problem?isFullScreen=true Library Fine | HackerRankHelp your library calculate fees for late books!www.hackerrank.com Your local library needs your help! Given the expected and actual return dates for a library book, create a program that calculates the fine (if any). The fee structure is as follows:If the book is returned on..

[해커랭크] Sherlock and Squares https://www.hackerrank.com/challenges/sherlock-and-squares/problem?isFullScreen=true Sherlock and Squares | HackerRankFind the count of square numbers between A and Bwww.hackerrank.com Watson likes to challenge Sherlock's math ability. He will provide a starting and ending value that describe a range of integers, inclusive of the endpoints. Sherlock must determine the..

[해커랭크] Append and Delete https://www.hackerrank.com/challenges/append-and-delete/problem?isFullScreen=true Append and Delete | HackerRankCan you convert $s$ to $t$ by performing exactly $k$ operations?www.hackerrank.com You have two strings of lowercase English letters. You can perform two types of operations on the first string:Append a lowercase English letter to the end of the string.Delete t..

1. CORS 란?Cross-Origin Resource Sharing 의 약자로, 웹 브라우저에서 다른 출처(도메인, 프로토콜, 포트)의 리소스에 접근할 수 있도록 허용하는 메커니즘FE(브라우저) → BE(API 서버) 요청을 할 때, 도메인/포트/프로토콜이 다르면 "Cross-Origin" 요청이 됩니다.보안 때문에 브라우저는 기본적으로 이를 차단해요.서버가 **“나는 이 출처(origin)에서 오는 요청을 허용한다”**라고 응답해줘야 브라우저가 통과시킵니다.=> 한마디로 말해서, BE API를 아무나 호출할 수 없도록 브라우저 보안 표준상 CORS 에러를 발생시켜 차단.=> 개발계에서는 편하려고 * 열어두고(모든 도메인에서 오는 요청을 다 허용), 운영계에서는 필요한 출처만 허용해둠.Access-C..

[해커랭크] Extra Long Factorials https://www.hackerrank.com/challenges/extra-long-factorials/problem?isFullScreen=true Extra Long Factorials | HackerRankCalculate a very large factorial that doesn't fit in the conventional numeric data types.www.hackerrank.com The factorial of the integer , written , is defined as: Calculate and print the factorial of a given integer.For example, if , we calculate ..