#define SOMECONST

#undef SOME

using System;

public class Program

{

    public static void Main()

    {

        // Console.WriteLine("Hello World Multiply " + MultiplyPositiveNos(6, 9));

        Console.WriteLine("Hello World Divide " + DividePositiveNos(3, 33));

        /*

​

// SomeType<AfceHummingBird> someType = new SomeType<AfceHummingBird>(6){ SomeStr = "hi" };

SomeType<AfceHummingBird> someType = new SomeType<AfceHummingBird>(6);

Console.WriteLine(someType.ToString());

<AllowUnsafeBlocks>true</AllowUnsafeBlocks>

double i = 6.6f;

double i_ = 6.1f;

unsafe {

    someType.PrintNo(&i, &i_);

}

        */

    }

    public static int MultiplyPositiveNos(int a, int b, int res = 0)

    {

        if(!(a >= 0) && !(b >= 0))

        {

            return 0;

        }

​

        if (a == 1)

        {

            // Console.WriteLine("A ");

            return b;

        }

​

        if (b == 1)

        {

            // Console.WriteLine("B ");

            // return a;

            if (res > 0)

            {

                return res;

            }

            else

            {

                return a;

            }

        }

        if (res == 0)

        {

            res = a;

        }

​

        var result = a + res;

        b--;

​

        // Console.WriteLine(result);

        return MultiplyPositiveNos(a, b, result); 

        //Console.WriteLine(result);

        //return result;

    }

    // abstract

    // lets say a by b or a / b, let a be greater 8, 2, 0

    public static int DividePositiveNos(int a, int b, int counter = 0)

    {

        if(a > b)

        {}

        else

        {

            //write swap swap(a, b){}

            Swap(ref a, ref b);

        }

        if(a == 0)

        {

            return 0;

        }

        if(b == 0)

        {

            // -1 for infinity

            return -1;

        }

​

        a = a - b;

        counter++;

        // b--;

​

        // Console.WriteLine(counter);

        if(a >= b)

        {

            return DividePositiveNos(a, b, counter);

        }

        return counter;

        //Console.WriteLine(result);

        //return result;

    }

    public static void Swap(ref int a, ref int b)

    {

        int c = b;

        b = a;

        a = c;

    }

}

​

/*

    public class SomeType<T> : Listener<T> where T : IBird

    {

        private int _someMesg;

​

        // public T type { get; set; }

​

        public SomeType(int someMesg) : base(new AfceHummingBird())

        {

            _someMesg = someMesg;

            // T someVar;

        }

​

        public string ToString(int num)

        {

            SomeStr = "xyz";

            return num.ToString();

        }

​

        public override string ToString()

        {

            // this.ToString();

            return _someMesg.ToString() + " plus.";

        }

​

        public override sealed void PrintMessage(string message)

        {

​

        }

​

        unsafe public void PrintNo(double* no, double* no_)

        {

​

// #error Some err

#warning Some warn

            // Console.WriteLine("No is " + no);

            Console.WriteLine((long) no);

            Console.WriteLine((long) no_);

#if SOMECONST

            Console.WriteLine("Running SomeConst.");

#elif SOME

            Console.WriteLine("Running Some.");

#else

            Console.WriteLine("Not running SomeConst.");

#endif

​

        }

    }

    public class Listener<T> where T : IBird

    {

        public Listener(AfceHummingBird afceHummingBird)

        {

            afceHummingBird.Message += PrintMessage;

        }

​

        public virtual void PrintMessage(string message)

        {

            Console.WriteLine($"{GetType().Name} heard - {message}");

        }

​

        protected string SomeStr { get; set; }

    }

    */

public class Singleton

{

    public static Singleton _instance;

    public static object lockObject;

    private Singleton()

    {

        // steps for the class

    }

    public Singleton Instance()

    {

        if(_instance != null)

        {

            return _instance;

        }

        lock(lockObject)

        {

            if(_instance != null)

            {

                return _instance;

            }

            _instance = new Singleton();

            return _instance;

        }

    }

}