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 C++14 (GCC 5.4.1) (judge verdict: Wrong Answer)

#include<bits/stdc++.h>
using namespace std;
long gcd(long a,long b){
  if(a%b == 0)return b;
  else{

    return gcd(b,a%b);
  }
}

int main(){
  long n;
  long m;
  cin >> n >> m;
  vector<long>a(n);
  int i;
  for(i=0;i<n;i++){
    cin >> a[i];
  }

  long tmp = a[0];
  for(i=1;i<n;i++){
    if(tmp >= a[i]){
      tmp = tmp/gcd(tmp,a[i])*a[i];
    }else{
      tmp = tmp/gcd(a[i],tmp)*a[i];
    }
  }
  cout << 2*m/tmp - m/tmp<<endl;
}