Problem:
Score : 400 points

Problem Statement

Given are a sequence A= {a_1,a_2,......a_N} of N positive even numbers, and an integer M.

Let a semi-common multiple of A be a positive integer X that satisfies the following condition for every k (1 \leq k \leq N):

There exists a non-negative integer p such that X= a_k \times (p+0.5).

Find the number of semi-common multiples of A among the integers between 1 and M (inclusive).

Constraints

1 \leq N \leq 10^5

1 \leq M \leq 10^9

2 \leq a_i \leq 10^9

a_i is an even number.

All values in input are integers.

Input

Input is given from Standard Input in the following format:

N M
a_1 a_2 ... a_N

Output

Print the number of semi-common multiples of A among the integers between 1 and M (inclusive).

Sample Input 1

2 50
6 10

Sample Output 1

2

15 = 6 \times 2.5

15 = 10 \times 1.5

45 = 6 \times 7.5

45 = 10 \times 4.5

Thus, 15 and 45 are semi-common multiples of A. There are no other semi-common multiples of A between 1 and 50, so the answer is 2.

Sample Input 2

3 100
14 22 40

Sample Output 2

0

The answer can be 0.

Sample Input 3

5 1000000000
6 6 2 6 2

Sample Output 3

166666667

Solution in Python (3.4.3) (judge verdict: Wrong Answer)

n, m = map(int, input().split())
a_li = list(map(int, input().split()))
a_li = [a // 2 for a in a_li]

from fractions import gcd
def lcm(x, y):
    return (x * y) // gcd(x, y)

def even_or_odd(a):
    a_parity = 'even' if a % 2 == 0 else 'odd'
    return a_parity

a_lcm = 1
a_parity = even_or_odd(a_li[0])
for a in a_li:
    if a_parity != even_or_odd(a):
        a_parity = 'irregular'
        break
    a_lcm = lcm(a, a_lcm)
lcm_parity = even_or_odd(a_lcm)
if a_parity == 'irregular' or a_lcm > m or a_parity != lcm_parity:
    ans = 0
else:
    ans = m // a_lcm
    ans = ans // 2 + 1 if ans % 2 == 1 else ans // 2
print(ans)