Kolakoski

Score: 92.22 (pass)

#!perl -l
($/,$b)=@ARGV;for(0..999){$;=$_%2?$b:$/;$k.=$;x(substr($k,$_,1)||$;)}print substr$k,0,pop

Score: 103.25 (pass)

#!perl -l
$/=shift;$b=shift;$k=$/x$/;for(1..999){$k.=($_%2?$b:$/)x(substr($k,$_,1)or$b)}print substr($k,0,pop)

Score: 104.25 (pass)

#!perl -l
$/=shift;$b=shift;$k=$/x$/;for(1..999){$k.=($_%2?$b:$/)x(substr($k,$_,1)or$b)}print substr($k,0,pop);

Score: 106.28 (pass)

#!perl -l
$a=shift;$b=shift;$k=$a x$a;for(1..999){$k.=($_%2?$b:$a)x(substr($k,$_,1)or$b)};print substr($k,0,pop);

Score: 109.29 (pass)

#!perl -l
$c=pop;$b=pop;$a=pop;$k=$a x$a;for(1..500){$k .=($_%2?$b:$a)x(substr($k,$_,1)or$b)};print substr($k,0,$c);