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 Ruby (2.3.3) (judge verdict: Runtime Error)

# 速くなるかどうか実験
n, m = gets.split.map(&:to_i)
a = gets.split.map(&:to_i)
a0 = a[0]
d = 1
while a0 % 2 == 0 do
  a0 /= 2
  d *= 2
end
if a.any? {|v| v % d != 0 || (v / d) % 2 == 0}
  puts 0
else
  half_lcm = a.inject(:lcm) / 2
  puts (m / half_lcm + 1) / 2
end