I am often finding myself in a situation where I want to sort a small number of elements. By small, I mean 3 or 4. I am probably correct in thinking that with such small problem sets I would want to use some type of explicit or direct method rather than invoking a sort function. 2 is trivial, 3 elements is still pretty simple but above 4 items or so and I’m starting to prefer the simplicity of just running insertion sort.
Up to how many elements can I expect a benefit to coding up a inline void sort_n(int *list)? 4? 5? 6?
In this topic, sorting int array with only 3 elements, there are two solutions for sorting 3 elements provided. One has more comparisons while the other minimizes comparisons but is more complicated. On a modern architecture, which would come out on top for speed?
Have a look at sorting networks.
A few links:
http://en.wikipedia.org/wiki/Sorting_network
http://www.cs.uky.edu/~lewis/essays/algorithms/sortnets/sort-net.html
Fastest sort of fixed length 6 int array