import java.io.*;
public class TestFunction{
 	  public static void main(String[] args) throws IOException{
    	InputStreamReader in=new InputStreamReader(System.in); 
 		BufferedReader bin=new BufferedReader(in);
    	float x,y;
System.out.println("xֵ");
	x=Integer.parseInt(bin.readLine());
	if(x<=0)
y=-x;
else if(x>0&&x<=30)
y=4*x+8;
else if(x>30)
				y=x-10;
System.out.println("x="+x);
	System.out.println("y="+y);
}
}
