Scanf.scanf "%d %d" (fun a b ->
    let judge k =
        let rec loop a =
            if a mod 10 = 0 then loop (a / 10) else abs a >= 1 && abs a <= 9
        in
        if a = 0 then false else loop k
    in
    if a mod 100 = 0 && b mod 100 = 0 && judge a && judge b then
        Printf.printf "%d\n" (a * b / 10)
    else
        let q = a * b in
        if q >= -99999999 && q <= 99999999 then Printf.printf "%d\n" q
            else print_endline "E"
)