#include<bits/stdc++.h>
using namespace std;

#define cout cerr
#define rep(i,a,b) for(int i=(a);i<=(b);++i)
#define per(i,a,b) for(int i=(a);i>=(b);--i)

typedef long long ll;
typedef pair<int,int> pii;
#define FR first
#define SE second

inline void rd(int &x){
	x=0;char ch=getchar();int f=1;
	while(ch<'0'||ch>'9'){
		if(ch=='-')f=-1;
		ch=getchar();
	}
	while(ch>='0'&&ch<='9'){
		x=x*10+ch-'0';
		ch=getchar();
	}
	x*=f;
}


int n;ll L;
#define Maxn 300010

ll gcd(ll a,ll b){
	if(!b)return a;
	return gcd(b,a%b);
}

ll a[Maxn];
typedef pair<ll,ll> pll;
pll A[65];int cnt;

void run(int x){
	int pre=cnt;
	A[x-1].FR=A[x].FR;
	A[x-1].SE=gcd(A[x-1].SE,A[x].SE);
	rep(i,x,cnt-1)A[i]=A[i+1];cnt--;
}

int main(){
	while(~scanf("%d%lld",&n,&L)){
		if(n==0&&L==0)break;
		cnt=0;
		rep(i,1,n)scanf("%lld",&a[i]);a[++n]=1;
		sort(a+1,a+n+1);n=unique(a+1,a+n+1)-a-1;
		for(int i=1,lst;i<=n;i=lst+1){
			ll g=a[i]-a[i-1];
			lst=i;while(lst+1<=n&&a[lst]*2>a[lst+1]){
				lst++;
				g=gcd(g,a[lst]-a[lst-1]);
			}
			A[++cnt]=pll(a[lst],g);
		}
		while(true){
			bool fl=true;
			rep(i,1,cnt){
				if(A[i].SE<A[i-1].FR){
					run(i);
					fl=false;
					break;
				}
				if(A[i].FR%A[i].SE==0&&i>1&&A[i-1].FR%A[i-1].SE==0){
					run(i);
					fl=false;
					break;
				}
			}
			if(fl)break;
		}
		if(A[1].SE==2)A[1].SE=1;
		ll res=0;
		rep(i,1,cnt)res+=(A[i].FR-A[i-1].FR)/A[i].SE;
		printf("%lld\n",res);
	}
	return 0;
}