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#include <bits/stdc++.h>
using namespace std;
//{
#define FOR(i,a,b) for(int i=(a);i<(b);++i)
#define FORD(i, a, b) for(int i = (a); i >= (b); --i)
#define VAR(v, i) __typeof(i) v=(i)
#define all(v) (v).begin(),(v).end()
#define FORE(i, c) for(VAR(i, (c).begin()); i != (c).end(); ++i)


#define PII pair<int,int>
#define st first
#define nd second
#define pb push_back
#define lint long long int
#define VI vector<int>

#define sim template < class c
#define ris return * this
#define dor > debug & operator <<
#define eni(x) sim > typename \
  enable_if<sizeof dud<c>(0) x 1, debug&>::type operator<<(c i) {
sim > struct rge { c b, e; };
sim > rge<c> range(c i, c j) { return rge<c>{i, j}; }
sim > auto dud(c* x) -> decltype(cerr << *x, 0);
sim > char dud(...);
struct debug {
~debug() { cerr << endl; }
eni(!=) cerr << boolalpha << i; ris; }
eni(==) ris << range(begin(i), end(i)); }
sim, class b dor(pair < b, c > d) {
  ris << "(" << d.first << ", " << d.second << ")";
}
sim dor(rge<c> d) {
  *this << "[";
  for (auto it = d.b; it != d.e; ++it)
	*this << ", " + 2 * (it == d.b) << *it;
  ris << "]";
}
};
//{
#define imie(...) " [" << #__VA_ARGS__ ": " << (__VA_ARGS__) << "] "

#define make( x) int (x); scanf("%d",&(x));
#define make2( x, y) int (x), (y); scanf("%d%d",&(x),&(y));
#define make3(x, y, z) int (x), (y), (z); scanf("%d%d%d",&(x),&(y),&(z));
#define make4(x, y, z, t) int (x), (y), (z), (t); scanf("%d%d%d%d",&(x),&(y),&(z),&(t));
#define makev(v,n) VI (v); FOR(i,0,(n)) { make(a); (v).pb(a);} 
#define IOS ios_base::sync_with_stdio(0)
#define HEAP priority_queue

#define read( x) scanf("%d",&(x));
#define read2( x, y) scanf("%d%d",&(x),&(y));
#define read3(x, y, z) scanf("%d%d%d",&(x),&(y),&(z));
#define read4(x, y, z, t) scanf("%d%d%d%d",&(x),&(y),&(z),&(t));
#define readv(v,n) FOR(i,0,(n)) { make(a); (v).pb(a);}
#define jeb() fflush(stdout);
//}


const int mod = 1e9 + 7;
const int max_n = 300005;

int r[max_n];
int ind[max_n];
int mind[max_n];
int rozne;

int dp[max_n];

int fen[2][2][300005];

void add(int co, int gdzie, int rem, int dec) {
	//cerr << "DODAJE co=" << co <<" gdzie="<< gdzie << " rem=" << rem << "dec= " << dec << endl; 
	while (gdzie <= rozne) {
		fen[rem][dec][gdzie] = (fen[rem][dec][gdzie] + co)%mod;
		gdzie += gdzie & (-gdzie);
	}
}

int ask(int gdzie, int rem, int dec) {
	//cerr << "PYTAM " << gdzie << " rem=" << rem << "dec= " << dec << endl; 
	int ans = 0;
	while (gdzie > 0) {
		ans += fen[rem][dec][gdzie];
		gdzie -= gdzie & (-gdzie);
		ans %= mod;
	}
	return ans;
}

int main() {
	make(n);
	makev(v, n);
	lint pref = 0;
	vector<PII> vr;
	vr.pb({0,n});
	FOR(i,0,n) {
		pref += v[i];
		r[i] = pref % mod;
		vr.pb({r[i],i});
	}
	sort(all(vr));
	rozne = 0;
	int act = -1;
	FOR(i,0,n+1) {
		if (i == 0 || (vr[i].st != vr[i-1].st)) {
			rozne++;
			ind[vr[i].nd] = rozne;
		} else {
			ind[vr[i].nd] = ind[vr[i-1].nd];
		}
	}
	FOR(i,0,n+1) mind[i] = rozne + 1 - ind[i];
	FOR(i,0,n+1) {
		//cerr << r[i] << " " << ind[i] << " " << mind[i] << endl;
	}

	dp[0] = 1;
	add(dp[0], ind[n], 0, 0);
	add(dp[0], mind[n], 0, 1);
	FOR(i,0,n) {
		dp[i+1] = (ask(ind[i], r[i] % 2, 0) + ask(mind[i] - 1, 1-(r[i]%2), 1))%mod;
		//cerr << "dp["<<(i+1) <<"] = " <<dp[i+1] << endl; 
		add(dp[i+1], ind[i], r[i] % 2 , 0);
		add(dp[i+1], mind[i], r[i] % 2 , 1);
	}
	printf("%d\n", dp[n]);
}
/*
j pasuje i <=> r[i] <= r[j] && r[i] == r[j] % 2 lub r[i] > r[j] && r[i] != r[j] % 2

dp[j] = sum dp[i] { po i < j, r[i] <= r[j] && r[i]%2 == r[j] % 2} + sum dp[i] { po i < j , r[i] > r[j] 
*/