var n,p,i,c,j:longint; f,g:text;  v:array[1..100] of integer;
function cmmdc(n,i:longint):longint;
 begin
  for j:=1 to n do
  if n>i then
  begin
  cmmdc:=i mod n;
  n:=i;
  cmmdc:=n;
  end
  else
  cmmdc:=n mod i;
  i:=n;
  cmmdc:=i;
  end;


begin
assign(f,'frac.in'); reset(f);
assign(g,'frac.out'); rewrite(g);
read(f,n,p);
for j:=1 to n do
begin
if cmmdc(i,n)=1 then
v[c]:=n;
end;

writeln(v[p]);


close(f); close(g);
end.