C#

int rate = 0;
int hours = 0;

while (rate == 0)
{
    Console.Write("Enter rate: ");
    if (!int.TryParse(Console.ReadLine(), out rate))
        Console.WriteLine("Invalid input");
}
while (hours == 0)
{
    Console.Write("Enter hours: ");
    if (!int.TryParse(Console.ReadLine(), out hours))
        Console.WriteLine("Invalid input");
}

int amount = (hours * rate);
Console.Clear();
Console.WriteLine("Rate = {0}, Hours = {1}{2}{2}Amount = {3}",
    rate, hours, Environment.NewLine, amount);
              
Console.ReadLine();

public static T[] AddElements<T>(T[] currentArray, params T[] element)
{
    T[] result = new T[currentArray.Length + element.Length];
    Buffer.BlockCopy(currentArray, 0, result, 0, currentArray.Length);
    for (int i = 0; i < element.Length; i++)
        result[currentArray.Length + i] = element[i];
    return result;
}

public static T[] AddElements<T>(T[] currentArray, params IEnumerable<T>[] elements)
{
    List<T> resultList = new List<T>(currentArray);
    foreach (IEnumerable<T> item in elements)
        resultList.AddRange(item);
    return resultList.ToArray();
}

byte[] currentArray = new byte[] { 0, 1, 2, 3, 4 };
byte elementA = 5;
byte elementB = 6;
byte elementC = 7;
currentArray = AddElements(currentArray, elementA);
currentArray = AddElements(currentArray, elementB, elementC);
byte[] elementsA = new byte[] { 8, 9, 10 };
byte[] elementsB = new byte[] { 11, 12, 13 };
List<byte> elementsC = new List<byte>() { 14, 15, 16 };
currentArray = AddElements(currentArray, elementsA);
currentArray = AddElements(currentArray, elementsB, elementsC);

DirectoryInfo di = new DirectoryInfo(@"c:\XXTemp");
FileInfo[] fil = di.GetFiles();

string[] picFiles = Directory.GetFiles(@"D:\PICS");
foreach (string picFile in picFiles)
{
  pictureBox1.Image = Image.FromFile(picFile);
  MessageBox.Show("Press OK for next picture...");
}