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#include<iostream>
#include<vector>
using namespace std;using ll=long long;
const int P=1e9+7;
int n;int main()
{ios::sync_with_stdio(0),cin.tie(0);cin>>n;vector<ll> x(n+1);for(int i=1;i<=n;i++){cin>>x[i];x[i]^=x[i-1]; }ll ans=x[n]%P;ll p=1;for(int i=n-1;i>=1;i--){ans=(ans+(2*x[i]%P*p%P))%P;p=p*3%P;}cout<<ans<<"\n";return 0;
}