Problem:
Score : 100 points

Problem Statement

Takahashi has K 500-yen coins. (Yen is the currency of Japan.)
If these coins add up to X yen or more, print Yes; otherwise, print No.

Constraints

1 \leq K \leq 100

1 \leq X \leq 10^5

Input

Input is given from Standard Input in the following format:

K X

Output

If the coins add up to X yen or more, print Yes; otherwise, print No.

Sample Input 1

2 900

Sample Output 1

Yes

Two 500-yen coins add up to 1000 yen, which is not less than X = 900 yen.

Sample Input 2

1 501

Sample Output 2

No

One 500-yen coin is worth 500 yen, which is less than X = 501 yen.

Sample Input 3

4 2000

Sample Output 3

Yes

Four 500-yen coins add up to 2000 yen, which is not less than X = 2000 yen.

Solution in OCaml (4.02.3) (judge verdict: Accepted)

open Batteries
open BatPrintf

let scan fmt f =
  BatScanf.sscanf (read_line ()) fmt f

let scan_list cnv =
  read_line ()
  |> BatString.split_on_char ' '
  |> List.map cnv

let rec zip xs ys =
  match xs, ys with
  | [], _ -> []
  | _, [] -> []
  | x::xs, y::ys ->
    (x, y) :: zip xs ys

let (k, x) = scan "%d %d" BatTuple.Tuple2.make

let () =
  printf "%s\n"
    (if x <= k * 500 then
       "Yes"
     else
       "No")