java（计算梯形面积）

class Lader{ double above,bottom,height; Lader(){} Lader(double a,double
b,double h){ above=a; bottom=b; height=h; } public void setAbove(double a) {
above=a; } public void setBottom(double b) { bottom=b; } public void
setHeight(double h) { height=h; } double computeArea(){
return(above+bottom)*height/2.0; } } public class Example4_3{ public static void
main(String args[]){ double area1=0,area2=0; Lader laderOne,laderTwo;
laderOne=new Lader(); laderTwo=new Lader(10,88,20); laderOne.setAbove(16);
laderOne.setBottom(26); laderOne.setHeight(100); laderTwo.setAbove(300);
laderTwo.setBottom(500); area1=laderOne.computeArea();
area2=laderTwo.computeArea();
System.out.println("laderOne的above,bottom,height:"+laderOne.above+","+laderOne.
bottom+","+laderOne.height); System.out.println("laderOne的面积:"+area1);
System.out.println("laderTwo的above,bottom,height:"+laderTwo.above+","+laderTwo.
bottom+","+laderTwo.height); System.out.println("laderTwo的面积:"+area2);
}
}