@test = qw|1 11 21 1211 111221 312211 13112221 1113213211
           31131211131221 13211311123113112211|;

##</code><code>##

$s=1;print"$s\n";for(2..10){@n=split//,$s;my@r;$c=$n[0];$l=0;while(@n){$n=shift@n;if($n==$c){$l++}else{push@r,[$l,$c];$c=$n;$l=1;}}push@r,[$l,$c];$s =join"",map{"$_->[0]$_->[1]"}@r;print"$s\n";}