static void Main(string[] args)
{
int sayi1 = 12;
int sayi2 = 10;
int sayi3 = 5;
int sayi4 = 2;
DortIslem dortIslem = new DortIslem();
dortIslem.toplama(sayi1, sayi2);
dortIslem.cikarma(sayi2, sayi3);
dortIslem.carpma(sayi3, sayi4);
dortIslem.bolme(sayi2, sayi4);
}