算圆面积和周长的class Circle
{
final static double PI=3.14;
public Circle(double radius)
{
public double area()
{
double area=PI*radius*radius;
return area;
}
public double perimeter()
{
double perimeter=2*PI*radius;
return perimeter;
}
}
}
class Circledemo
{
public static void main(String args[])
{
Circle cir=new Circle(3.5);
System.out.println("圆的面积:"+cir.Area());
System.out.println("圆的周长:"+cir.perimeter());
}
}
{
final static double PI=3.14;
public Circle(double radius)
{
public double area()
{
double area=PI*radius*radius;
return area;
}
public double perimeter()
{
double perimeter=2*PI*radius;
return perimeter;
}
}
}
class Circledemo
{
public static void main(String args[])
{
Circle cir=new Circle(3.5);
System.out.println("圆的面积:"+cir.Area());
System.out.println("圆的周长:"+cir.perimeter());
}
}
{
final static double PI=3.14;
private double radius;
public Circle(double radius)
{
this.radius=radius;
}
public double area()
{
double area1=PI*radius*radius;
return area1;
}
public double perimeter()
{
double perimeter1=2*PI*radius;
return perimeter1;
}
}
class Circledemo
{
public static void main(String args[])
{
Circle cir=new Circle(3.5);
System.out.println("圆的面积:"+cir.area());
System.out.println("圆的周长:"+cir.perimeter());
}
}帮你改了一下,应该可以了
public double area()
^
Circledemo.java:16:';'expected
}
^
public Untitled2() {
}public static void main(String args[])
{
Untitled1 cir=new Untitled1(3.5);
System.out.println("圆的面积:"+String.valueOf(cir.area()));
System.out.println("圆的周长:"+String.valueOf(cir.perimeter()));
}
}
package com.borland.samples.welcome;public class Untitled1 {
final static double PI=3.14;
double radius=0.0;
public Untitled1(double radius) {
this.radius=radius;
}public double area()
{
double area = PI * radius * radius;
return area;
} public double perimeter() {
double perimeter = 2 * PI * radius;
return perimeter;
}
}
我给你做了一下,你自己看吧,只是为了调试,我把名字给改了,你自己改回去也可以。你自己改回去也可以。