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 (3.8.2) (judge verdict: Accepted)

import math
def LCM(a, b):
    g = math.gcd(a, b)
    return a * b // g

N, M = map(int, input().split())
A = list(map(int, input().split()))
A = list(set(A))
N = len(A)
a0 = A[0]
div = 1
while a0 % 2 == 0:
    div *= 2
    a0 //= 2

for i in range(1, N):
    a = A[i] % div
    b = A[i] // div
    if (b % 2 == 0) or (a != 0):
        print(0)
        exit()

for i in range(N):
    A[i] //= 2

if N > 1:
    lcm = LCM(A[0], A[1])
    for i in range(2, N):
        lcm = LCM(lcm, A[i])

if N == 1:
    lcm = A[0]

ans = M // lcm
if ans % 2 == 1:
    print(ans // 2 + 1)
else:
    print(ans // 2)