填空题 [说明]
下面程序输出一个矩形面积，以及矩形区域上的假想的作物产量。
[Java程序]
public class Mainjava
public static void main(String[] args)
Lot_size small = new Lot_size() ;
Lot_size medium = new Lot_size();
small.set (5,5,5,25) ;
medium.set (10,10,10, 50) ;
System.out.println("For a small lot of area "
+small.get_area () +"/n");
System.out.println("the actual crops are $"
+small.get_data2 () +" /n") ;
System.out.println("and ideal crops are $"
+small.get_data () +"/n") ;
System.out.println("For a medium lot of area"
+medium.get_area () +"/n");
system.out.println ("the actual crops are $ "
+medium.get_data2 () +"/n ");
System.out.println ("and ideal crops are $"
+medium.get_data () +"/n");


class Crop_assessment
private int actual_crop;
private int ideal_crop;
public void set(int in_actual,int in_ideal)
actual_crop = in_actual;
ideal_crop = in_ideal;

public int get_actual_crop () return (1) ;
public int get_ideal_crop() return (2) ;

class Lot_size
private int length;
private int width;
private Crop_assessment crop = (3) ;
public void set(int 1,int w,int a,int i)
length =1;
width = w;
crop.set (a,i) ;

public int get_area () return lengt h*width;
public int get_data() return (4) ;
public int get_data2 () return (5) ;