Stack and Queue in C#

Objective

Stack and queue is very useful in a program. For example, you want to process a group of object like queue (First In First Out), so you can use queue in this case. This tutorial will guide you how to use stack and queue in C# language.

Let's go

Stack

Naturally you can see stack very often. An example is you put files in a pile, so when you want to take a file, you need take it from top and go down. In programming, stack often uses in statement processing. With stack all operations is processed in the end of it. To use stack, C# provide an Stack class. Bellow is list of common members that provided by Stack class:

This example bellow show you how to work with stack:

//declare a stack with elements have type of int.
static Stack<int> int_stack = new Stack<int>();
 
static void Main(string[] args)
{
     //add elements to stack
      for (int i = 0; i < 6; i++)
      {              
           int_stack.Push(i);
           //print value
           Console.WriteLine("push value to stack " + i);
      }
 
      //print number of elements in stack
      Console.WriteLine("number of elements in stack " + int_stack.Count);
      //get each element from stack
      while(int_stack.Count>0){
      {
           int val = int_stack.Pop();
           //print value
           Console.WriteLine("pop value from stack " + val);
      }
      Console.ReadKey();
}

Here is output of the program:
push value to stack 0
push value to stack 1
push value to stack 2
push value to stack 3
push value to stack 4
push value to stack 5
number of elements in stack 6
pop value from stack 5
pop value from stack 4
pop value from stack 3
pop value from stack 2
pop value from stack 1
pop value from stack 0

Queue

In case you want to process a group of objects like a queue (First In First Out), you can do it with a queue. An example of queue is buying ticket, people must arrange in a queue and wait for his/her turn. In programming language, queue is very useful, especially with high performance system. C# provide a Queue class to implement a queue. Here is list of common members:

Here is example of how to work with queue:

//declare a queue with elements have type of int.
static Queue<int> int_queue = new Queue<int>();
 
static void Main(string[] args)
{
     //add elements to queue
     for (int i = 0; i < 6; i++)
     {
          int_queue.Enqueue(i);
          //print value
          Console.WriteLine("push value to stack " + i);
     }
 
     //print number of elements in queue
     Console.WriteLine("number of elements in queue " + int_queue.Count);
     //get each element from stack
     while(int_queue.Count>0){
          int val = int_queue.Dequeue();
          //print value
          Console.WriteLine("pop value from queue " + val);
     }
 
     Console.ReadKey();
}

The output of the program is:
push value to queue 0
push value to queue 1
push value to queue 2
push value to queue 3
push value to queue 4
push value to queue 5
number of elements in queue 6
pop value from queue 0
pop value from queue 1
pop value from queue 2
pop value from queue 3
pop value from queue 4
pop value from queue 5

Summary

In this tutorial we have shown you a very useful and important point in programming language in general, and C# language in private. Hope that you can investigate more carefully about that theme, and can do more with it.