Diademata

You are curious about the geographical distribution of CodeSignal users, so you have created a list of countries along with the number of registered users from each. Your task now is to calculate the number of users on each continent. The information about the countries is stored in a table countries, which has 3 columns: country: the name of the country;continent: the name of the continent wher..

You recently started working in the IT department of a large store. You were put in charge of the inventory database availableItems, which has the following structure: id: unique item ID;item_name: the name of the item;item_type: the type of the item.Note that it is possible for items that are of different types to have the same names. One of the most common operations performed on this database..

Your friend wants to become a professional tour guide and travel all around the world. In pursuit of this dream, she enrolled in tour guide school. The professors in this school turned out to be very demanding, and one of them gave your friend a difficult assignment that she has to finish over the weekend. Here's the task: Given a list of countries, your friend should calculate the average popul..

You are managing a small newspaper subscription service. Anyone who uses it can subscribe to a large number of different newspapers for a full year or just a half year. The information about subscriptions is stored in the full_year and half_year tables, which have the following structures: full_year:id: the unique subscription ID;newspaper: the newspaper's name;subscriber: the name of the subscr..

You're a math teacher at an elementary school. Today you taught your class basic arithmetic operations ("+", "-", "*", "/") and now you need to give the students some homework. You have a lot of expressions in the format a b = c, where a, b, and c are some integers and operation is one of the operations given above. Information about these expressions is stored in the table expressions, which ha..

Implement the missing code, denoted by ellipses. You may not modify the pre-existing code.Your professor gave the class a bonus task: Write a program that will check the answers for the latest test. The program will be given a table answers with the following columns: id - the unique ID of the question;correct_answer - the correct answer to the question, given as a string;given_answer - the answ..

You are managing a large website that uses a special algorithm for user identification. In particular, it generates a unique attribute for each person based only on their first and last names and some additional metadata. After analyzing the server logs today you found out that the website security has been breached and the data of some of your users might have been compromised. The users' info ..

A large amount of money was stolen today from the main city bank, and as the chief of police it's your duty to find the robber. You store information about your suspects in the table Suspect, which has the structure: id: unique suspect id;name: suspect first name;surname: suspect surname;height: suspect height;weight: suspect weight.You have already gathered some evidence and discovered the foll..

https://www.acmicpc.net/problem/1766 민오는 1번부터 N번까지 총 N개의 문제로 되어 있는 문제집을 풀려고 한다. 문제는 난이도 순서로 출제되어 있다. 즉 1번 문제가 가장 쉬운 문제이고 N번 문제가 가장 어려운 문제가 된다. 어떤 문제부터 풀까 고민하면서 문제를 훑어보던 민오는, 몇몇 문제들 사이에는 '먼저 푸는 것이 좋은 문제'가 있다는 것을 알게 되었다. 예를 들어 1번 문제를 풀고 나면 4번 문제가 쉽게 풀린다거나 하는 식이다. 민오는 다음의 세 가지 조건에 따라 문제를 풀 순서를 정하기로 하였다. N개의 문제는 모두 풀어야 한다. 먼저 푸는 것이 좋은 문제가 있는 문제는, 먼저 푸는 것이 좋은 문제를 반드시 먼저 풀어야 한다. 가능하면 쉬운 문제부터 풀어야 한다. 예..

A large amount of money was stolen today from the main city bank, and as the chief of police it's your duty to find the robber. You store information about your suspects in the table Suspect, which has the structure: id: unique suspect id;name: suspect first name;surname: suspect surname;height: suspect height;weight: suspect weight.You have already gathered some evidence and discovered the foll..