DailyQuiz
About today's quiz

Programming — Intermediate

A new quiz is published every day for this topic and level. Answer the questions, read the explanations, and complete the quiz to keep your streak alive.

Tips before you start

  • •Read every question carefully before answering. Some questions include subtle wording that changes the correct answer.
  • •Take your time on the first question. There is no time limit, but your total time is tracked for your statistics.
  • •After each answer, read the explanation. Even correct answers often include useful context you might not know.
  • •Come back tomorrow for a brand new quiz on the same topic. Daily practice is the most effective way to retain what you learn.
IntermediateTechnology
Today's questions

Today's quiz questions

These are the questions that make up today's quiz. Test your knowledge, see how much you know, and learn from the explanation behind every answer.

  1. 1.What is the Observer pattern?

    • •A security pattern for logging user actions
    • •A pattern where an object (subject) maintains a list of dependents (observers) that are notified on state changes
    • •A monitoring tool that watches for code changes
    • •A pattern where objects observe other objects' source code

  2. 2.What is a promise in JavaScript?

    • •A guarantee that code will run without errors
    • •A declaration that a variable will be assigned later
    • •A type of callback function
    • •An object representing the eventual completion or failure of an asynchronous operation

  3. 3.What is a closure in programming?

    • •A function that retains access to variables from an enclosing scope
    • •A function that closes all open database connections
    • •A method that prevents a class from being extended
    • •A loop that terminates when a condition is met

  4. 4.What is a hash table (or hash map)?

    • •A list sorted by hash values
    • •A table that stores encrypted data
    • •A data structure that maps keys to values through hashing
    • •A SQL table with indexed columns

  5. 5.Which of these is NOT a primitive data type in most languages?

    • •Boolean
    • •Float
    • •Array
    • •Integer

  6. 6.What is the purpose of an ORM (Object-Relational Mapping)?

    • •To optimize database queries automatically
    • •To map database tables to programming language objects, allowing database operations using code instead of raw SQL
    • •To convert object-oriented code to functional code
    • •To create visual representations of database schemas

  7. 7.What is a graph data structure?

    • •A database table with complex relationships
    • •A visual chart used for data visualization
    • •A collection of nodes (vertices) connected by edges, used to model relationships and networks
    • •A tree with more than two children per node

  8. 8.What is a deadlock?

    • •A loop that cannot be terminated by the user
    • •A program crash caused by infinite recursion
    • •A situation where two or more processes are blocked, each waiting for the other to release a resource
    • •A security lock on a database after detecting unauthorized access

  9. 9.Which sorting algorithm has average complexity O(n log n) and is considered efficient?

    • •QuickSort
    • •InsertionSort
    • •BubbleSort
    • •SelectionSort

  10. 10.What is a linked list?

    • •A list that can only store linked objects
    • •A linear data structure where elements are stored in nodes, each pointing to the next
    • •An array where elements are linked by their index
    • •A database table with foreign key relationships