replace multiplication with addition ^_^

+1 for documentation

i love the comments, good job)

author is paid for total number of lines/chars of code?)))

the hard way...

hard to read (and apparently) to debug, comments would be welcomed

very concise (condensed) but logical, although computational complexity may be reduced by keeping track of already taken instead of recalculating them each time from scratch

too much comments, but it is always better than absence of them (see ninja code around)!

great

good, better than mine

almost exact mine solution)

brilliant, I never thought that this can be done with so simple code (although it wad HARD to read)

like it

quite clear and "understandable"

here I witnessed a true "PYRAMID OF DOOM"))))
.
for such approach at work I would be punished and banned from coding))))