abstract class Shape
{
abstract float Area();
abstract void printArea();
}
class Rectangle extends Shape
{
int width;
int length;
public Rectangle(int newWidth,int newLength)
{
width=newWidth;
length=newLength;
}
public float Area()
{
return width*length;
}
public void printArea()
{
System.out.println("矩形的面积是："+width*length);
}
}
class Circle extends Shape
{
final float pi=3.14F;
int radius;
public Circle(int newRadius)
{
radius=newRadius;
}
public float Area()
{
return pi*radius*radius;
}
public void printArea()
{
System.out.println("圆形的面积是："+pi*radius*radius);
}
}
class ChouXiang
{
public static void main(String[] args)
{
Rectangle s1=new Rectangle(3,4);
Circle s2=new Circle(2);
s1.printArea();
s2.printArea();
//System.out.println("Hello World!");
}
}
为什么矩形的返回值是整型而不是单精度，怎么解决。。。。
先行谢过。
