public void SelectionSort() // ascending order
{

    for (int i = 1; i <= List.Count; i++) // go through the list
    {
        ListClass minimum = (ListClass)List[i-1];
        int min = i - 1;
        for (int j = i;j <= List.Count-1; j++)
        {
            ListClass cur = (ListClass)List[j];

            if (minimum.getNum() > cur.getNum())
                min = j; // min equals smallest in list j

        }
        swap(List, i-1, min); 
    }
    Console.WriteLine("Array after selection sort: ");
    foreach (ListClass cur in List)
    {
        cur.Display();
    }
public static void swap(ArrayList List, int x, int y)
{
    object temp = List[x];
    List[x] = List[y];
    List[y] = temp;
}
public void Display()
{
    foreach (ListClass cur in List)
    {
        cur.Display();
    }
}