> Your program in Guile Scheme which realizes an algorithm is not a
> derivative work of the program you read, which program is written in
> C.  Even in the case that your program realizes the same algorithm as
> the C program does.  The above official article of the US Copyright
> Office clearly states this.

That is only true, if you do not re-use any structure of the original
program that is not part of the algorithm.

If you want to be sure, you need a cleanroom re-implementation: Have
someone else read the code and write down the pure algorithm. Then
implement that without ever having seen the original code.
https://en.wikipedia.org/wiki/Clean_room_design

Best wishes,
Arne
-- 
Unpolitisch sein
heißt politisch sein
ohne es zu merken