組合せゲーム Subtraction の定義 (CGSuite)

Subtraction.cgs

class Subtraction extends ImpartialGame

    var lrset; // The subtraction set
    var n; // The heap size

    method Subtraction(Set lrset, Number n)
    end

    override method Options(Player player)
        return setof(Subtraction(lrset, n - k) for k in lrset where n - k >= 0);
    end

    override property ToString.get
        return "Subtraction(" + lrset.ToString + "," + n.ToString + ")";
    end

end