package tuxing2;

public abstract class tuxing {

? ? static int a = 4;

? ? static double π = 3.14;

? ? static int b = 5;

public abstract void Area();//面積

? ? public abstract void Perimeter();//周長

}

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package tuxing2;

public class Round extends tuxing {

@Override

public void Area() {//圓形的面積

// TODO Auto-generated method stub

? ? ? ? System.out.println("圓形的面積= "+π*a*a);

}

@Override

public void Perimeter() {//圓形的周長

// TODO Auto-generated method stub

System.out.println("圓形的周長= "+2*π*a);

}

}

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package tuxing2;

public class Rectangle extends tuxing {

@Override

public void Area() {//矩形的面積

// TODO Auto-generated method stub

System.out.println("矩形的面積= "+a*b);

}

@Override

public void Perimeter() {//矩形的周長

// TODO Auto-generated method stub

System.out.println("矩形的周長= "+(a+a+b+b));

}

}

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package tuxing2;

public class Test {

public static void main(String[] args) {

// TODO Auto-generated method stub

tuxing TX1 = new Round();

TX1.Area();

TX1.Perimeter();

tuxing TX2 = new Rectangle();

TX2.Area();

TX2.Perimeter();

}

}