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#include <bits/stdc++.h>
using namespace std;
#define REP(i,a,b) for (int i = (a); i <= (b); ++i)
#define REPD(i,a,b) for (int i = (a); i >= (b); --i)
#define FORI(i,n) REP(i,1,n)
#define FOR(i,n) REP(i,0,int(n)-1)
#define mp make_pair
#define pb push_back
#define pii pair<int,int>
#define vi vector<int>
#define ll long long
#define SZ(x) int((x).size())
#define DBG(v) cerr << #v << " = " << (v) << endl;
#define FOREACH(i,t) for (typeof(t.begin()) i=t.begin(); i!=t.end(); i++)
#define fi first
#define se second

const int mod = 1000000007;
const int N = 300300;
//const int M = 1<<3;
const int M = 1<<19;

/// input
int n;
int a[N], pref[N], dp[N];

/// ids
pii prefs[N];
int ids[N];

int T[2][M*2+13];
void add(int t0, int pos, int val) {
	//cerr << "adding (" << t0 << ") at position " << pos << " value " << val << "\n";
	pos += M;
	while (pos > 0) {
		T[t0][pos] += val;
		if (T[t0][pos] >= mod) T[t0][pos] -= mod;
		pos /= 2;
	}
	/*cerr << "T[" << t0 << "] =";
	FOR(i,M*2) {
		if (__builtin_popcount(i) == 1) cerr << " |";
		cerr << " " << T[t0][i];
	}
	cerr << "\n";*/
}
int get(int t0, int pos) {
	//cerr << "reading (" << t0 << ") on interval [0, " << pos << "] : ";
	pos += M;
	int ans = T[t0][pos];
	while (pos > 1) {
		if ((pos & 1) == 1) {
			ans += T[t0][pos-1];
			if (ans >= mod) ans -= mod;
		}
		pos /= 2;
	}
	//cerr << ans << "\n";
	return ans;
}

int main() {
	/// read input
	scanf("%d", &n);
	FORI(i,n) scanf("%d", &a[i]);
	FORI(i,n) pref[i] = (pref[i-1] + a[i]) % mod;
	
	/// prepare ids
	FOR(i,n+1) prefs[i] = mp(pref[i], i);
	sort(prefs,prefs+n+1);
	FOR(i,n+1) {
		ids[prefs[i].se] = i;
		if (i>0 && prefs[i].fi==prefs[i-1].fi) ids[prefs[i].se] = ids[prefs[i-1].se];
	}
	//FOR(i,n+1) cerr << "i = " << i << ", pref = " << pref[i] << ", id = " << ids[i] << "\n";
	
	dp[0] = 1;
	add(0, 0, 1);
	FORI(i,n) {
		/*int tmp_dp = 0;
		FOR(j,i) {
			if (pref[j] <= pref[i]) {
				if (pref[i]%2 == pref[j]%2) tmp_dp += dp[j];
			} else {
				if (pref[i]%2 != pref[j]%2) tmp_dp += dp[j];
			}
			if (dp[i] >= mod) tmp_dp -= mod;
		}*/
		dp[i] = (0LL + get(pref[i]%2, ids[i]) + get(1-pref[i]%2, n) - get(1-pref[i]%2, ids[i]) + mod) % mod;
		//cerr << "i = " << i << " : dp slow = " << tmp_dp << ", dp fast = " << dp[i] << "\n";
		add(pref[i]%2, ids[i], dp[i]);
	}
	printf("%d\n", dp[n]);
	return 0;
}