这个小问题麻烦大家了!
class Trangle{
double sideA,sideB,sideC,area,length;
boolean boo;
public Trangle(double a,double b,double c)
{
sideA=a;sideB=b;sideC=c;
if((a+b)>c&&(b+c)>a&&(a+c)>b)
{
boo=true;
}
else{
boo=false;
}
}
double getLength(){
length=sideA+sideB+sideC;
return length;
}
public double getArea()
{
if(boo)
{
double p=(sideA+sideB+sideC)/2.0;
area=Math.sqrt(p*(p-sideA)*(p-sideB)*(p-sideC));
return area;
}
else
{
System.out.println("不是一个三角形,不能计算面积");
return 0;
}
}
public void setABC(double a,double b,double c){
sideA=a;sideB=b;sideC=c;
if((a+b)>c&&(b+c)>a&&(a+c)>b)
{
boo=true;
}
else{
boo=false;
}
}
}
class Lader{
double above,bottom,height,area;
Lader(double a,double b,double h){
above=a;bottom=b;height=h;
double getArea() //不明白为什么这句会报错,有问题!
{
area=(a+b)*h/2;
return area;
}
}
}
class Circle{
double radius,area;
Circle(double r){
radius=r;
}
double getArea(){
area=3.14*r*r;
return area;
}
double getLength(){
length=3.14*2*r;
return length;
}
}
public class AreaAndLength{
public static void main(String args[]){
double length,area;
Circle circle=null;
Trangle trangle;
Lader lader;
circle(5.0);
trangle(3.0,4.0,5.0);
lader(1.0,2.0,3.0);
length=circle.getLength;
System.out.println("圆的周长:"+length);
area=circle.getArea;
System.out.println("圆的面积:"+area);
length=trangle.getlength;
System.out.println("三角形的周长:"+length);
area=trangle.getArea;
System.out.println("三角形的面积:"+area);
area=lader.getArea;
System.out.println("梯形的面积:"+area);
setABC(12.0,34.0,1.0);
area=trangle.getArea;
System.out.println("三角形的面积:"+area);
length=trangle.getLength;
System.out.println("三角形的周长:"+length);
}
}