Kolakoski

Score: 66.28 (pass)

#!perl -l
$l=pop;push@s,($_)x($s[$i++]||$_)for(@ARGV)x$l;print@s[0..--$l]

Score: 72.28 (pass)

#!perl -l
$l=pop;@t=(@ARGV)x$l;push@s,($_)x($s[$i++]||$_)for@t;$#s=--$l;print@s

Score: 89.24 (pass)

#!perl -l
for(($a,$b,$l)=@ARGV;$l--;($a,$b)=($b,$a)){push@s,($a)x($s[$p++]||$a)}print@s[0..--$p]