//implementation of gcd (greatest common divisor)
//author: Michal Pilipczuk
//XIV Secondary School, Warsaw, Poland

program gcd;
uses bignumber;
var hand_in:text;
a,b,w:string;
begin
    initialize;
    assign(hand_in,'/home/k03_a/michaj/.homepage/gcd.in');
    reset(hand_in);
    readln(hand_in,a);
    readln(hand_in,b);
    close(hand_in);
    if not((sprawdz(a)) and (sprawdz(b))) then
    writeln('WRONG INPUT')
    else
    begin
	a:=zmienw2(a,10);
	b:=zmienw2(b,10);
	w:=nwduj(a,b);
	writeln(zmien(w,10));
    end;
end.