#!perl -p s/./ord$&/sge;while($_){/.$/;$s=$&%2 .$s;$t=$v="";$t.=$v+$_/2|0,$v=$_%2*5 for/./g;s/^0// if$_=$t}$_=$s;s/(.)(.)?/([A,C],[G,T])[$1][$2]/ge