sub c {($a,$c)=@_;@c=@$c;grep$_,map{$a>$_?
  &{sub{$a-=$_*($b=int($a/$_));"$b x $_"}}:""} reverse @c}  

##</code><code>##

sub c{($a,$c)=@_;@c=@$c;grep$_,map{$a>$_?
  &{sub{$a-=$_*($b=int$a/$_);"$b x $_"}}:""}reverse@c}