class Program
{
    /// <summary>
    /// Divides given arguments.
    /// </summary>
    /// <returns> divident / divisor </returns>
    /// <exception cref="ArgumentException">divisor is 0</exception>
    /// <exception cref="DividentIsNegativeException">divident is negative</exception>
    /// <exception cref="ArgumentsAreZeroException">divident and divisor are 0</exception>
    public static float Divide(float divident, float divisor)
    {
        if (divident == 0 && divisor == 0) throw new ArgumentsAreZeroException();
        if (divident < 0) throw new DividentIsNegativeException(divident);
        if (divisor == 0) throw new ArgumentException();
        return divident / divisor;
    }

    static void Main(string[] args)
    {
        float a = 4, b = 2;
        try
        {
            Console.WriteLine($"{a}/{b}={Divide(a, b)}");
        }
        catch (ArgumentsAreZeroException)
        {
            Console.WriteLine("Divident and Divisor are 0");
        }
        catch (DividentIsNegativeException x)
        {
            Console.WriteLine($"Divident { x.Divident} is negative");
        }
        catch (ArgumentException)
        {
            Console.WriteLine("Divisor can't be 0");
        }
    }
}

class ArgumentsAreZeroException : ArgumentException
{
}

class DividentIsNegativeException : ArgumentException
{
    public float Divident { get; private set; }
    public DividentIsNegativeException(float divident) => this.Divident = divident;
}