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Java A - 1

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Java A - 2

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Java A - 4

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Java A - 5

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Java A - 6

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Java A - 7

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Java A - 8

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public Cirkel(double r) { radie = r; }

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public double yta() { return radie * radie * pi; }

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public static void main(String[] args) { Cirkel enCirkel = new Cirkel(10.0);

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Java A - 10

//Fil: Cirkel.java //Fil: Kvadrat.java public class Cirkel public class Kvadrat { { public final double pi = 3.14159; private double sida = 0; private double radie = 0; public Kvadrat(double a) public Cirkel(double r) { { sida = a; radie = r; } } public double yta() public double yta() { { return sida * sida; return radie * radie * pi; } } } public static void main(String[] args) { Cirkel enCirkel = new Cirkel(10.0);

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public class Main //Fil: Main.java { public static void main(String[] args) { Kvadrat kvadraten = new Kvadrat(3.0); Cirkel cirkeln = new Cirkel(10.0); System.out.println(kvadraten.yta()); System.out.println(cirkeln.yta()); } }

==> javac -g Main.java Kvadrat.java Cirkel.java ==> java Main 9.0 314.159 ==>

==> javac -g Main.java ==> java Main 9.0 314.159 ==>

Java A - 11

Java A - 12

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class Cirkel { public final double pi = 3.14159; private double radie = 0;

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public class Kvadrat { private double sida = 0;

public Cirkel(double r) { radie = r; }

public Kvadrat(double sida) { this.sida = sida; }

public double yta() { return radie * radie * pi; }

}

public static void main(String[] args) { Cirkel enCirkel = new Cirkel(10.0);

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} class Main { public static void main(String[] args) { Kvadrat kvadraten = new Kvadrat(3.0); Cirkel cirkeln = new Cirkel(10.0); System.out.println(kvadraten.yta()); System.out.println(cirkeln.yta()); } }

==> javac -O MinaKlasser.java ==> java Main 9.0 314.159 ==> ls *.class Kvadrat.class Cirkel.class Main.class

public class Kvadrat { private double sida = 0; public Kvadrat() { this(7.0); // Får endast förekomma på den } // första raden public Kvadrat(double sida) { this.sida = sida; }

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Java A - 13

Java A - 14

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