The solution time can vary quite a bit depending on the difficulty of the puzzle. 1 ms for a single puzzle for a program written in C could actually be fairly s

The solution time can vary quite a bit depending on the difficulty of the puzzle. 1 ms for a single puzzle for a program written in C could actually be fairly slow for an easy puzzle, but would be quite fast for a hard puzzle. (It would also depend, of course, on how fast a CPU and how much memory was being used to run the program.)