#include <bits/stdc++.h>

using namespace std;

void fastStd()
{
	ios_base::sync_with_stdio(0);
	cin.tie(NULL);
	cout.tie(NULL);
}

const int MOD = 1e9+7;

int n;
vector<int> arr;
vector<long long> minim;
vector<pair<long long, long long>> dp;
vector<pair<long long, long long>> dp2;

long long generate(bool plus, int index){
	if(index == n-1){
		if(plus){
			return dp[index].first;
		} else {
			return dp[index].second;
		}
	}
	if(plus){
		if(dp[index+1].first != -1 && dp[index+1].second != -1){
			dp[index].first = (dp[index+1].first + dp[index+1].second) % MOD;
		} else if(dp[index+1].first != -1) {
			dp[index].first = (dp[index+1].first + generate(false, index+1)) % MOD;
		} else if(dp[index+1].second != -1){
			dp[index].first = (generate(true, index+1) + dp[index+1].second) % MOD;
		} else {
			dp[index].first = (generate(true, index+1) + generate(false, index+1)) % MOD;
		}
		return dp[index].first % MOD;
	} else {
		if(dp[index+1].first != -1){
			dp[index].second = dp[index+1].first;
 		} else {
 			dp[index].second = generate(true, index+1);
 		}
 		return dp[index].second % MOD;
	}
}

long long generate2(bool plus, int index){
	if(index == 1){
		if(plus){
			return dp2[index].first;
		} else {
			return dp2[index].second;
		}
	}
	if(plus){
		if(dp2[index-1].first != -1 && dp2[index-1].second != -1){
			dp2[index].first = (dp2[index-1].first + dp2[index-1].second) % MOD;
		} else if(dp2[index-1].first != -1) {
			dp2[index].first = (dp2[index-1].first + generate2(false, index-1)) % MOD;
		} else if(dp2[index-1].second != -1){
			dp2[index].first = (generate2(true, index-1) + dp2[index-1].second) % MOD;
		} else {
			dp2[index].first = (generate2(true, index-1) + generate2(false, index-1)) % MOD;
		}
		return dp2[index].first % MOD;
	} else {
		if(dp2[index-1].first != -1){
			dp2[index].second = dp2[index-1].first;
 		} else {
 			dp2[index].second = generate2(true, index-1);
 		}
 		return dp2[index].second % MOD;
	}
}


int main()
{
	#ifndef ONLINE_JUDGE
		freopen("input.txt", "r", stdin);
		freopen("output.txt", "w", stdout);
	#endif

	scanf("%d", &n);
	arr.resize(n);
	long long sum = 0;
	for(int &x : arr){
		scanf("%d", &x);
		sum += x % MOD;
		sum %= MOD;
	}
	if(n == 1){
		printf("%d\n", arr[0]);
		return 0;
	}
	minim.resize(n);
	dp.resize(n, {-1, -1});
	dp[n-1] = {1,1};
	dp2.resize(n, {-1, -1});
	dp2[1] = {1, 1};
	long long x = generate(true, 1);
	x = generate(false, 1);
	x = generate2(true, n-1);
	x = generate2(false, n-1);
	long long ans = (sum * ((dp[1].first + dp[1].second) % MOD)) % MOD;
	// printf("%lld\n", ans);
	for(int i = 1; i < n; i++){
		minim[i] = ((dp[i].second % MOD) * (dp2[i].second % MOD)) % MOD;
		ans -= ((arr[i] * minim[i] % MOD) * 2) % MOD;
		ans = (ans + MOD) % MOD;
		// printf("%lld %lld %lld %lld\n", dp[i].first, dp[i].second, minim[i], ans);
	}
	printf("%lld\n", ans);


	
	return 0;
}
#include <bits/stdc++.h>
using namespace std;
using ll=long long;
#define fi first
#define se second
#define rep(i,n) for(int i=0;i<n;i++)
#define all(v) v.begin(),v.end()
#define pb push_back
template<class T,class U>
inline bool chmax(T &a,U b){
    if(a<b){
        a=b;
        return true;
    }
    return false;
}
template<class T,class U>
inline bool chmin(T &a,U b){
    if(a>b){
        a=b;
        return true;
    }
    return false;
}
constexpr int INF=1000000000;
constexpr ll llINF=3000000000000000000;
constexpr int mod=998244353;
constexpr double eps=1e-8;
const double pi=acos(-1);
int dx[]={0,1,0,-1},dy[]={1,0,-1,0};
int Random(int mi,int ma){
    random_device rnd;
    mt19937 mt(rnd());//32bit
    //[mi,ma]
    uniform_int_distribution<int>engine(mi,ma);
    return engine(mt);
}
/*
vector<vector<ll>>C,sC;
void init_comb(int n,int m){
    C.resize(n+1,vector<ll>(m+1,0));
    sC.resize(n+1,vector<ll>(m+1,0));
    C[0][0]=1;
    for(int i=1;i<=n;i++){
        C[i][0]=1;
        for(int j=1;j<=m;j++){
            C[i][j]=(C[i-1][j-1]+C[i-1][j])%mod;
        }
    }
    rep(i,n+1){
        rep(j,m){
            sC[i][j+1]=(sC[i][j]+C[i][j])%mod;
        }
    }
}*/
ll gcd(ll a,ll b){
    while(a%b){
        a%=b;
        swap(a,b);
    }
    return b;
}
ll lcm(ll a,ll b){
    return a/gcd(a,b)*b;
}
bool isprime(int a){
    if(a==1)return false;
    for(int i=2;i*i<=a;i++){
        if(a%i==0)return false;
    }
    return true;
}
vector<int>primes;
void init_prime(int n){
	primes.push_back(2);
    for(int i=3;i<=n;i+=2){
        bool f=true;
        for(int j:primes){
            if(j*j>i)break;
            if(i%j==0){
                f=false;
                break;
            }
        }
        if(f)primes.push_back(i);
    }
}
ll modpow(ll a,ll b){
    ll res=1;
    while(b){
        if(b&1){
            res*=a;
            res%=mod;
        }
        a*=a;
        a%=mod;
        b>>=1;
    }
    return res;
}
vector<ll>inv,fact,factinv;
void init_fact(int n){
    inv.resize(n+1);
    fact.resize(n+1);
    factinv.resize(n+1);
    inv[0]=0;
    inv[1]=1;
    fact[0]=1;
    factinv[0]=1;
    for(ll i=1;i<=n;i++){
        if(i>=2)inv[i]=mod-((mod/i)*inv[mod%i]%mod);
        fact[i]=(fact[i-1]*i)%mod;
        factinv[i]=factinv[i-1]*inv[i]%mod;
    }
}
ll _inv(ll a,ll m=mod){
    //gcd(a,m) must be 1
    ll b=m,u=1,v=0;
    while(b){
        ll t=a/b;
        a-=t*b;swap(a,b);
        u-=t*v;swap(u,v);
    }
    u%=m;
    if(u<0)u+=m;
    return u;
}
ll comb(int a,int b){
    if(a<b)return 0;
    if(a<0)return 0;
    return fact[a]*factinv[a-b]%mod*factinv[b]%mod;
}
ll multicomb(int a,int b){
    return comb(a+b-1,b);
}
void solve(){
    int n,a[20];
    cin>>n;
    rep(i,n)cin>>a[i];
    int ans=(1<<30);
    rep(s,1<<(n-1)){
        int X=0,O=a[0];
        rep(i,n-1){
            if((s>>i)&1){
                O|=a[i+1];
            }
            else{
                X^=O;
                O=a[i+1];
            }
        }
        X^=O;
        chmin(ans,X);
    }
    cout<<ans<<endl;
}
int main(){
    cin.tie(0);ios::sync_with_stdio(false);
    //int t;cin>>t;while(t--)
    solve();
    return 0;
}