using System;

public class Program

{

    public static void Main()

    {

        // Lesson 14: static

​

        // can be used with members or classes

        // members: e.g., fields and methods

​

        // Main is an example of a static method

        // It does need an object to be run/called

​

        // Another example comes from the Math library

​

        Math.Pow(4, 2);

​

​

        // This call to Pow() does not require a math object

        // But it does require that you reference the class 

        // Notice that the class name has taken the place of the object name

        // (Hint: Math is capitalized)

​

        // Math m = new Math();

        //m.pow()

​

        // This does not work because Math is a static class

        // You can not instantiate static classes

​

        Console.WriteLine(Physics.numberOfPeopleThatLiveOnMars);

​

        Physics.calculatePhysicsStuff();

​

        Console.WriteLine(Math.PI);

    }

}

​

public static class Physics

{

    public static int numberOfPeopleThatLiveOnMars = 35000;

​

    public static void calculatePhysicsStuff()

    {

        // do stuff

    }

}

​

//• You would then use the static methods in this class directly:

//double squareRoot = Math.Sqrt(16); // squareRoot will be 4.0

//double powerResult = Math.Pow(2, 3); // powerResult will be 8.0

​

​

            // Lesson 14

​

​

// • Develop a static class named CurrencyConverter that includes a static method for converting an amount from one currency to another.

// Provide methods for setting exchange rates and converting between different currencies.

// Consider using enums for the currency types.

// You may need to check current exchange rates online to complete this program.

class CurrencyConverter

{

    // Static Integer

    public static int AUD;

    public static int USD;

    // Instance Integer

​

}

​

​

public class FieldDemo

{

    static void Main(string[] args)

    {

        // Create instances of the Counter class

        Counter instance1 = new Counter();

        Counter instance2 = new Counter();

        Counter instance3 = new Counter();

        // Print the counters for each instance

        Console.WriteLine($"Static Counter: {Counter.sCount}");

        Console.WriteLine($"Instance 1: {instance1.iCount}");

        Console.WriteLine($"Instance 2: {instance2.iCount}");

        Console.WriteLine($"Instance 3: {instance3.iCount}");

    }

}

class Counter

{

    // Static integer field

    public static int sCount;

    // Instance integer field

    public int iCount;

    public Counter()

    {

        sCount += 1;

        this.iCount += 1;

    }

}

​

// Explain why sCount and iCount have different values despite having the same reassignment statements in the Counter constructor method.

//      iCount starts and stops counting for each new instance. sCount continues counting through each instance?