Introduction to std::queue

C++ is a versatile and powerful programming language widely used in various software development fields. One of its key features is the Standard Template Library (STL), which provides a range of useful data structures, including std::queue. A queue is a First-In-First-Out (FIFO) data structure, which means the first element added is the first one to be removed.

What is std::queue?

std::queue is a container adapter that provides the functionality of a queue, with its elements arranged in a FIFO order. It is part of the C++ Standard Library and is useful for managing collections of elements where the first element added should be the first one to be removed.

Key Features of std::queue

  • FIFO Structure: First-In-First-Out order of elements.
  • Basic Operations: Supports essential queue operations like push, pop, front, and back.
  • Container Adapter: Typically built on top of other containers like std::deque or std::list.

How to Declare and Initialize a std::queue

Here are some basic ways to declare and initialize a queue:

#include <iostream>
#include <queue>
#include <list>

int main() {
    std::queue<int> queue1; // Empty queue of integers
    std::queue<int, std::deque<int>> queue2; // Queue using deque as underlying container
    std::queue<int, std::list<int>> queue3; // Queue using list as underlying container

    return 0;
}

Basic Operations on std::queue

Adding Elements

Elements can be added to the queue using the push method: