C# program to implement stack

Here's a C# program that implements a stack data structure:

using System;

public class Stack
{
    private T[] items;
    private int top;

    public Stack(int capacity)
    {
        items = new T[capacity];
        top = -1;
    }

    public bool IsEmpty()
    {
        return top == -1;
    }

    public bool IsFull()
    {
        return top == items.Length - 1;
    }

    public void Push(T item)
    {
        if (IsFull())
        {
            throw new InvalidOperationException("Stack is full");
        }

        items[++top] = item;
    }

    public T Pop()
    {
        if (IsEmpty())
        {
            throw new InvalidOperationException("Stack is empty");
        }

        return items[top--];
    }

    public T Peek()
    {
        if (IsEmpty())
        {
            throw new InvalidOperationException("Stack is empty");
        }

        return items[top];
    }
}

public class Program
{
    public static void Main()
    {
        Stack stack = new Stack(5);

        stack.Push(1);
        stack.Push(2);
        stack.Push(3);
        stack.Push(4);
        stack.Push(5);

        Console.WriteLine("Stack peek: " + stack.Peek());

        while (!stack.IsEmpty())
        {
            Console.WriteLine("Popped: " + stack.Pop());
        }
    }
}

In this program, the 'Stack' class is a generic class that represents a stack. It uses an array to store the stack items, and the 'top' variable keeps track of the index of the top item in the stack.

The stack has the following methods:

• 'IsEmpty()': Checks if the stack is empty.
• 'IsFull()': Checks if the stack is full.
• 'Push(T item)': Pushes an item onto the stack.
• 'Pop()': Pops and returns the top item from the stack.
• 'Peek()': Returns the top item from the stack without removing it.

In the Main method, we create a Stack object with a capacity of 5. We then push some integers onto the stack and print the top item using Peek(). Finally, we pop all the items from the stack and print them.