program Project2;
{$APPTYPE CONSOLE}
uses
  SysUtils;

var m,n: integer;
function NSD(var a,b: longint): longint;
var l: integer;
    c: longint;
begin
   while (a<>0)and(b<>0)do
      if a>b then
         a:=a-b
      else
         b:=b-a;
   if a<>0 then NSD:=a
   else
      NSD:=b;
end;
begin
   readln(m,n);
   writeln(NSD(m,n));
   readln(m);
end.