%h=@h=(M,1000,CM,900,D,500,CD,400,C,100,XC,90,L,50,XL,40,X,10,IX,9,V,5,IV,4,I,1,);
$r=join'|',sort{length($b)-length($a)}keys%h;
<>;
$_=<>;
s/$r/$s+=$h{$&}/ge;
exit!print"ERROR"if$s>3999;
while($s){
	for(@h){
		if($h{$_}&&$s>=$h{$_}){
			print$_;
			$s-=$h{$_};
			last;
		}
	}
}