using System;

public class Program

{

    public static void Main()

    {

        int x= 21;

        int y= 65;

        int s= 12;

        int w= 73;

        int f= 80;

        int g= 31;

        int q= -20;

        int resultat= x / y - s * w + f * g - q / w / q;

        Console.WriteLine(resultat);

    }

}