import java.util.*; public class Main{ public static void main(String[] args){ Scanner in = new Scanner(System.in); int w,n; double x,y; while(in.hasNext()){ w = in.nextInt(); y = in.nextDouble(); x = in.nextDouble(); n = in.nextInt(); System.out.println(calAge(w,y,x,n)); } } public static int calAge(int w,double y, double x,int n){ for(int i=0;i<n;i++){ y = (y+1)*(1-x) + 21*x; } return (int)Math.ceil(y); } }
