public abstract class ArithmeticTable {

    protected int columns;
    protected int rows;
    protected int[][] table;
    protected String operand;

    public ArithmeticTable(int columns, int rows) {

        this.columns = columns;
        this.rows = rows;
        table = new int[columns][rows];

        for (int x = 0; x < columns; x++) {
            for (int y = 0; y < rows; y++) {
                table[x][y] = evaluate(x, y);
            }
        }
    }

    public abstract int evaluate(int a, int b);

    public void print() {

        System.out.println("Operand: " + operand);

        for (int i = 0; i < columns; i++) {
            for (int j = 0; j < rows; j++) {
                System.out.print(evaluate(i, j) + " ");
            }
            System.out.println();

        }

        System.out.println();
        System.out.println();

    }
}


////////////////////////////////////////////////////////////////



public class MultiplicationTable extends ArithmeticTable{

    public MultiplicationTable(int columns, int rows) {
        super(columns, rows);
        operand = "*";
    }

    @Override
    public int evaluate(int a, int b) {
        return a * b;
    }

}
///////////////////////////////////////////////////////////


public class DivisionTable extends ArithmeticTable {

    public DivisionTable(int columns, int rows) {
        super(columns, rows);
        operand = "/";

    }

    @Override
    public int evaluate(int a, int b) {
        if(b == 0){
            return 0;
        }
        return a / b; // Kommer ske en heltalsdivision, dvs 5/9 = 0, 9/5 = 1.
                        // Måste använda double för att dividera "på riktigt",
                        // dvs 5/9 = 0,555..
    }

}

/////////////////////////////////////////////////////


public class SubtractionTable extends ArithmeticTable{

    public SubtractionTable(int columns, int rows) {
        super(columns, rows);
        operand = "-";
    }

    @Override
    public int evaluate(int a, int b) {
        return a - b;
    }

}
////////////////////////////////////////////////


public class AdditionTable extends ArithmeticTable{

    public AdditionTable(int columns, int rows) {
        super(columns, rows);
        operand = "+";
    }

    @Override
    public int evaluate(int a, int b) {
        return a + b;
    }

}
/////////////////////////////////