방구석 개발자의 실험실

[해커랭크] Cut the sticks

[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

[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

[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

[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 ..

[해커랭크] Utopian Treehttps://www.hackerrank.com/challenges/utopian-tree/problem?isFullScreen=true Utopian Tree | HackerRankPredict the height of the tree after N growth cycles.www.hackerrank.com The Utopian Tree goes through 2 cycles of growth every year. Each spring, it doubles in height. Each summer, its height increases by 1 meter.A Utopian Tree sapling with a height of 1 meter is planted at th..

https://www.hackerrank.com/challenges/designer-pdf-viewer/problem?isFullScreen=true Designer PDF Viewer | HackerRankHelp finding selection area in PDF Viewer.www.hackerrank.com When a contiguous block of text is selected in a PDF viewer, the selection is highlighted with a blue rectangle. In this PDF viewer, each word is highlighted independently. For example:There is a list of character h..

[해커랭크] The Hurdle Racehttps://www.hackerrank.com/challenges/the-hurdle-race/problem?isFullScreen=true= 0." data-og-host="www.hackerrank.com" data-og-source-url="https://www.hackerrank.com/challenges/the-hurdle-race/problem?isFullScreen=true" data-og-url="https://www.hackerrank.com/challenges/the-hurdle-race/problem" data-og-image="https://scrap.kakaocdn.net/dn/dKRyz2/hyZuHOizvE/TVca6Q4SVpvHH5CC9..

[해커랭크] Climbing the Leaderboardhttps://www.hackerrank.com/challenges/climbing-the-leaderboard/problem?isFullScreen=true Climbing the Leaderboard | HackerRankHelp Alice track her progress toward the top of the leaderboard!www.hackerrank.com An arcade game player wants to climb to the top of the leaderboard and track their ranking. The game uses Dense Ranking, so its leaderboard works like this:T..