java实验答案解读

Triangle.java
package figure;
public class Triangle
{
private double a,b,c;
public Triangle(double x,double y,double z)
{
a = x;
b = y;
c = z;
}
public void get()
// TODO Auto-generated method stub
int i,j,k=0;
for(i=2;i<100;i++){
if(i==2)
System.out.println(i);
i++;
for(j=2;j<i;j++)
{
if(i%j!=0)
k=1;
}
if(k==1)
System.out.println(i);
}
}
求1！+2！+……+20！
public class jiecheng {
public static void main(String[] args) {
int i,sum=0,k;
for(i=1;i<=20;i++)
{
k=ji(i);
sum=k+sum;
}System.outFra bibliotekprint(sum);
public class Circle
{
private double r;
private double PI = 3.14;
public Circle(double x)
{
r = x;
}
public double get()
{
return r;
}
public void set(double x)
{
r = x;
import java.applet.*;
import java.awt.*;
public class myapplet extends Applet
{
public void paint(Graphics g)
{
String str="";
for(char a='α';a<'ω';a++)
{
str+=a;
if(i==(a*a*a+b*b*b+c*c*c))
System.out.println(i);
}
}
}
输出如下：
153
370
371
407
打印出100以内素数：
public class sushu {
/**
* @param args
*/
public static void main(String[] args) {
}
g.drawString(str, 2, 10);
}
}
实验二
设计一个名为figure的图形软件包（package）。包中包含三角形、矩形、圆三个类。要求：（1）每个类都要构造方法并为成员设置get和set方法；（2）每个类都要有计算周长和面积的成员方法；（3）完成该软件包后的编码后，在另一个包的含有main方法的类中编写代码，分别使用图形软件包中的三个类，生成三个对象，并打印出其周长和面积。
{
for(int k=n-1;k>=i;k--)
{
System.out.print(" ");
}
for(int j=1;j<=2*i-1;j++)//打印*
{
System.out.print("*");
}
System.out.println();
}
}
}
编写程序，命令行窗口输出希腊字母表。（希腊字母表开始为α，最后一个为ω）
{
}
public void set(double x,double y,double z)
{
a = x;
b = y;
c = z;
}
public double Perimeter()
{
double per = a + b + c;
return per;
}
public double Area()
{
double area = 0;
}
public double Perimeter()
{
double per = 2*(length + width);
return per;
}
public double Area()
{
double area = length * width;
return area;
}
}
Circle.java
package figure;
}
public double Perimeter()
{
double per = 2*(PI * r);
return per;
}
public double Area()
{
double area = PI*(double)Math.pow(r,2);
return area;
}
}
figureTest.java
实验一
水仙花数：
class shuixianhua
{//水仙花数
public static void main(String arg[])
{
int i,a,a1,b,b1,c;
for(i=100;i<1000;i++)
{
a=i%10;
a1=i/10;
b=a1%10;
b1=a1/10;
c=b1%10;
double p=(a+b+c)/2;
double s = p*(p-a)*(p-b)*(p-c);
area = (double)Math.sqrt(s);
return area;
}
}
Rectangle.java
package figure;
public class Rectangle
{
private double length;
package Test;
import figure.Circle;
import figure.Rectangle;
import figure.Triangle;
public class figureTest
private double width;
public Rectangle(double l,double w)
{
length = l;
width = w;
}
public void get()
{
}
public void set(double l,double w)
{
length = l;
width = w;
}
static int ji(int n)
{
if(n==1)
return 1;
else
return ji(n-1)*n;
}
}
习题2.6
public class Test{
public static void main(String[] args)//第19题,打出图形.菱形
{
int n=3;
for(int i=1;i<=n;i++)