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)

import fractions
from functools import reduce
def lcm_base(x, y):
    return (x * y) // fractions.gcd(x, y)

def lcm(*numbers):
    return reduce(lcm_base, numbers, 1)
    
def factorization(n):
    arr = []
    temp = n
    for i in range(2, int(-(-n**0.5//1))+1):
        if temp%i==0:
            cnt=0
            while temp%i==0:
                cnt+=1
                temp //= i
            arr.append([i, cnt])

    if temp!=1:
        arr.append([temp, 1])

    if arr==[]:
        arr.append([n, 1])

    return arr

N, M = map(int,input().split())
A = list(map(int,input().split()))
B = []

for i in range(N):
        '''
        a = factorization(A[i]) 
        B.append(A[i] // (2**a[0][1]))
        '''
        while A[i] % 2 == 0:
                A[i] //= 2

a = lcm(*A)
#print(a)

if a > M or a==1:
        print(0)
        exit(0)
'''
for i in range(a,M+1,a*2):
    #print(i)
    i = float(i)
    flag = 0
    for j in A:
        #print((i / j)-0.5)
        if ((i / j)-0.5).is_integer() == False:
            flag = 1
    if flag == 0 and 0 <= (i / j)-0.5:
        break
'''
print(int((M-a) // (a*2) + 1))