in reply to
Re: Golf for unique digits
in thread Golf for unique digits
perl -nlE"say 0+s/(.)(?!.*\1)//g"
tye++ ... but I'm stuck to understand how it works?
According to perlop:
Searches a string for a pattern, and if found, replaces that pattern with the replacement text and returns the number of substitutions made.
How does the number of substitutions made equate to the number of characters left after the substitutions?
(?!..) = not followed by!
every cipher is exactly once the last of it's kind! =)
Of course! Thanks.
This seems to work just as well?
perl -nlE"say s/(.)(?!.*\1)//g"
Results (341 votes),