#include<bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef unsigned long long ull;
typedef pair<ll,ll> P;
#define fi first
#define se second
#define mkp make_pair
#define pb emplace_back
#define popcnt __builtin_popcountll
const ll mod = 998244353;
inline ll read(){
	ll x=0, f=1; char ch=getchar();
	while(ch<'0' || ch>'9') { if(ch=='-') f=-1; ch=getchar(); }
	while(ch>='0' && ch<='9') x=x*10+ch-'0', ch=getchar();
	return x*f;
}
inline int lg2(int x){ return 31^__builtin_clz(x); }
inline ll lg2(ll x){ return 63^__builtin_clzll(x); }
inline ll qpow(ll a,ll b){
	ll ans=1, base=a;
	while(b){
		if(b&1) ans=ans*base%mod;
		base=base*base%mod; b>>=1;
	}
	return ans;
}
int n; ll a[25];
void init(){ }
void procedure(){
	n=read();
	for(ll i=1;i<=n;i++) a[i]=read();
	sort(a+1, a+n+1);
	ll x=read();
	ll ans=0;
	for(int i=0;i<(1<<n);i++){
		if(i&1){
			ll cur=x;
			for(int j=n-1;j>=0;j--){
				if((i>>j)&1) cur %= a[j+1];
			}
			ans=max(ans, cur);
		}
	}
	printf("%lld\n", ans);
}
int main(){
	#ifdef LOCAL
		assert(freopen("input.txt","r",stdin));
		assert(freopen("output.txt","w",stdout));
	#endif
	ll T=1;
	init();
	while(T--) procedure();
	return 0;
}