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#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>

/*
#pragma GCC target("avx2")
#pragma GCC optimization("Ofast")
#pragma GCC optimization("unroll-loops")
*/

using namespace __gnu_pbds;
using namespace std;

#define mp make_pair
#define eb emplace_back
#define pb push_back
#define e1 first
#define e2 second
#define vt vector
#define maxi(x,y) x=max(x,y)
#define mini(x,y) x=min(x,y)
#define size(x) (int)x.size()
#define all(r) begin(r),end(r)
#define fastio ios_base::sync_with_stdio(0);cin.tie(0);cout.tie(0)
#define cx real()
#define cy imag()
#define precision(x) setprecision(x)<<fixed
#define time chrono::high_resolution_clock().now().time_since_epoch().count()
#ifndef DEBUG
#define DEBUG false
#endif
#define dbg if(DEBUG)

typedef long long ll;
typedef long double ld;
typedef complex<long double> cplx;
typedef unsigned int uint;
typedef unsigned long long ull;
typedef vt<int> vi;
typedef vt<vi> vvi;
typedef vt<bool> vb;
typedef vt<vb> vvb;
typedef vt<char> vc;
typedef vt<vc> vvc;
typedef vt<string> vs;
typedef vt<vs> vvs;
typedef vt<ll> vll;
typedef vt<vll> vvll;
typedef vt<ld> vld;
typedef vt<vld> vvld;
typedef vt<cplx> vcplx;
typedef vt<vcplx> vvcplx;

template<typename T>
using ordset=tree<T,null_type,less<T>,rb_tree_tag,tree_order_statistics_node_update>;

template<typename T1,typename T2>
ostream& operator<<(ostream &os,pair<T1,T2>& VAR){
	os<<"("<<VAR.e1<<","<<VAR.e2<<")";
	return os;
}

template<typename T>
ostream& operator<<(ostream& os,vt<T>& VAR){
	os<<"[";
	for(int i=0;i<size(VAR)-1;i++)
		os<<VAR[i]<<",";
	if(size(VAR))
		os<<VAR.back();
	os<<"]";
	return os;
}

template<typename T>
istream& operator>>(istream& is,complex<T>& VAR){
	T value;
	is>>value;
	VAR.real(value);
	is>>value;
	VAR.imag(value);
	return is;
}

const bool TESTS=false;

const int mod=1000'000'000+7;

void add(int& a,int b){
	a+=b;
	if(a>=mod)
		a-=mod;
}

int sum(int a,int b){
	a+=b;
	if(a>=mod)
		a-=mod;
	return a;
}

void mul(int& a,ll b){
	a=(a*b)%mod;
}

int prod(int a,ll b){
	return (a*b)%mod;
}

int neg(int a){
	if(a==0)
		return 0;
	return mod-a;
}

const int MAXN=3e5+10;

int t[2][2][MAXN];
int total[2][2];

void update(int p,int k,int x,int y){
	add(total[x][y],k);
	for(;p<MAXN;p=(p|(p-1))+1)
		add(t[x][y][p],k);
}

int query(int p,int x,int y){
	int ans=0;
	for(;p;p=(p&(p-1)))
		add(ans,t[x][y][p]);
	return ans;
}

void solve(){
	int n;
	cin>>n;
	vi a(n),b(n),c(n),p(n);
	vt<pair<int,int>> vals(n);
	ll tot=0;
	for(int i=0;i<n;i++){
		cin>>a[i];
		tot+=a[i];
		b[i]=tot%2;
		vals[i]={tot%mod,i};
		c[i]=(tot/mod)%2;
	}
	sort(all(vals));
	int prv=0;
	int cnt=1;
	for(auto& x:vals){
		if(x.e1!=prv){
			prv=x.e1;
			cnt++;
		}
		p[x.e2]=cnt;
	}
	update(1,1,0,0);
	int odp=1;
	for(int i=0;i<n;i++){
		int x=b[i];
		int y=c[i];
		int lwb00=query(p[i],x,y);
		int lwb11=query(p[i],x^1,y^1);
		int upb00=sum(total[x][y^1],neg(query(p[i],x,y^1)));
		int upb11=sum(total[x^1][y],neg(query(p[i],x^1,y)));
		odp=sum(sum(lwb00,lwb11),sum(upb00,upb11));
		update(p[i],odp,x,y);
	}
	cout<<odp<<'\n';
}

int32_t main(){
	fastio;
	if(TESTS){
		int TEST_COUNT;
		cin>>TEST_COUNT;
		for(int i=0;i<TEST_COUNT;i++)
			solve();
	}
	else
		solve();
	return 0;
}