It has been a while since I have implemented a sorting algorithm - I should probably have implemented these a little bit earlier than I have done :)

Today I bring you the C sharp version of the selection sort I posted earlier. To mix it up a bit htough this implementation is in reverse.

1. Find the largest number in the sequence
2. If it is larger than the number at the end of the array, swap them
3. Find the next largest number
4. If it is larger than the next number along from the end of the array, swap them
5. Repeat steps 3 and 4 until all the numbers have been sorted.

Here is the code:

/// <summary>
/// Performs a selection sort on an array of ints.
/// </summary>
/// <param name="array">The array to sort.</param>
static void selection_sort(ref int[] array)
{
    int limit = array.Length - 1;
    while(limit > 0)
    {
        //find the index with the maximum value
        int max_index = 0; //set the max to the first element in the array
        //don't search the first element in the array, we have already done that on the line above
        for(int i = limit - 1; i > 0; i--)
        {
            if(array[i] > array[max_index])
                max_index = i;
        }
        if(array[max_index] > array[limit])
        {
            //we have found an index with a high value than the current limit
            swap_places(ref array, max_index, limit);
        }

        limit--;
    }
}

Full Source Code (pastebin) Link to binary (MD5: ef5e0f15c9bc181d36b193160e3f8ad9 SHA1: ad49eb97675ca6ec9cc9dfebb63fbe03cfa27534)

Next up: Insertion sorting.