Tabla de Multiplicar, Numeros Primos

TABLA DE MULTIPLICAR 

using System;

using System.Collections.Generic;

using System.Linq;

using System.Text;

using System.Threading.Tasks;

namespace Tarea2

{

    class Program

    {

        static void Main(string[] args)

        {

            int vi, vf, vm, r, con;

           

            Console.WriteLine("ingrese un valor");

            vi = Convert.ToInt16(Console.ReadLine());

            Console.WriteLine("ingrese un valor");

            vf = Convert.ToInt16(Console.ReadLine());

            Console.WriteLine("ingrese un valor");

            vm = Convert.ToInt16(Console.ReadLine());

            Console.WriteLine("Bucle for");

            for (int i = vi; i <= vf; i++)

            {

                r = vm * i;

                Console.WriteLine(vm + "*" + i + "=" + r);

            }

            Console.ReadLine();

            Console.WriteLine("Bucle Do While ");

            con = 0;

            do

            {

                con = con+1;

                r = vm * con;

                Console.WriteLine(vm + "*" + con + "=" + r);

            } while (con<=vf);

            Console.ReadLine();

            Console.WriteLine("Bucle While ");

            con = 0;

            while (con<=vf)

            {

                con = con+1;

                r = vm * con;

                Console.WriteLine(vm + "*" + con + "=" + r);

            }

            Console.ReadLine();

        }

    }

}

10 PRIMEROS NUMEROS PRIMOS

using System;

using System.Collections.Generic;

using System.Linq;

using System.Text;

using System.Threading.Tasks;

namespace _10prinumprimos

{

    class Program

    {

        static void Main(string[] args)

        {

            int con = 0, i = 0, j, a, acu = 0;

            Console.WriteLine("10 Primeros Numeros Primos");

            do

            {

                i = i + 1;

                con = 0;

                for (j = 1; j <= i; j++)

                {

                    a = i % j;

                    if (a == 0)

                    {

                        con = con + 1;

                    }

                }

                if (con == 2)

                {

                    Console.WriteLine("" + i);

                    acu = acu + 1;

                }

               

            } while (acu < 10);

            Console.ReadLine();

        }

               

    }

}