program hello;
var x, a, b, p, s, v, h: integer;
begin
    readln(x);
    a := x div 10;
    b := x mod 10;
    if (x mod 2 <> 0) and (x mod 5 = 0) then
        begin
        s := a + b;
        writeln(s);
        end
        else
        begin
        p := a * b;
        writeln(p);
    end;
end.