uses crt;
var  a,b,i,j,d,s,t,t1:longint;
begin
clrscr;
write('nhap so a:');readln(a);
write('nhap so b:');readln(b);
d:=1;
if a>b then
 for i:=b to a do
 begin
  s:=0;
  for j:=1 to i do
   if i mod j=0 then s:=s+1;
  if s=2 then d:=d*i;
 end;
if a<b then
 for i:=a to b do
 begin
  s:=0;
  for j:=1 to i do
   if i mod j=0 then s:=s+1;
  if s=2 then d:=d*i;
 end;
t1:=d mod 100;
t1:=(t1 mod 10) + (t1 div 10);
write(t1);
readln;
end.

uses crt;
var a,b,i,s: int64;
function nt(n: int64): boolean;
var i: int64;
begin
    if n<=1 then exit(false);;
    for i:=2 to round(sqrt(n)) do if n mod i = 0 then exit(false);
    exit(true);
end;
begin
clrscr;
    readln(a,b);
    s:=1;
    for i:=a to b do if nt(i) then s:=s*i;
    writeln(s);
    write((s mod 10) + (s mod 100 div 10));
    readln
end.