stack in c++

A stack in C++ is a data structure that follows the Last-In-First-Out (LIFO) principle. It is a container that allows insertion and removal of elements only at one end, called the top.

To implement a stack in C++, follow these steps:

  1. Define a class for the stack: Start by defining a class for the stack. This class will hold the necessary member variables and member functions to manipulate the stack.

  2. Declare the member variables: Inside the class, declare a private dynamic array to store the elements of the stack. Additionally, declare a variable to keep track of the top of the stack.

  3. Implement the constructor: Define a constructor for the stack class. The constructor should initialize the top variable to -1 and allocate memory for the dynamic array.

  4. Implement the push() function: The push() function adds an element to the top of the stack. It should increment the top variable and store the new element in the appropriate position of the dynamic array.

  5. Implement the pop() function: The pop() function removes the top element from the stack. It should decrement the top variable and return the element that was removed.

  6. Implement the top() function: The top() function returns the element at the top of the stack without removing it. It should simply return the element at the index specified by the top variable.

  7. Implement the isEmpty() function: The isEmpty() function checks if the stack is empty. It should return true if the top variable is -1 (indicating an empty stack), or false otherwise.

  8. Implement the isFull() function (optional): The isFull() function checks if the stack is full. This is necessary only if you have a fixed-size stack. It should return true if the top variable is equal to the maximum size of the stack, or false otherwise.

  9. Test the stack: Finally, create an instance of the stack class and use its member functions to test its functionality. Add elements using the push() function, remove elements using the pop() function, and retrieve the top element using the top() function. Don't forget to check for empty or full stack conditions using the isEmpty() and isFull() functions, if applicable.

Remember to include the necessary header files and use proper syntax and conventions while implementing the stack in C++.