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#include <bits/stdc++.h>
using namespace std;
int n,ite;
long long a[300005],pre[300005],dp[300005],
	t0[1200005],t1[1200005],iii[300005];
pair<long long,int>pr[300005];
long long sump,sumn;
const int p = 1000000007;

void u0(int v,int tl,int tr,int it,int ii)
{
	if(tl == tr && tl == it)
	{
		t0[v] = dp[ii];
		return;
	}
	if(it < tl || tr < it)
		return;
	int tm = (tr + tl) / 2;
	u0(2 * v,tl,tm,it,ii);
	u0(2 * v + 1,tm + 1,tr,it,ii);
	t0[v] = t0[2 * v] + t0[2 * v + 1];
	t0[v] %= p;
}
long long q0(int v,int tl,int tr,int l,int r)
{
	if(r < l)
		return 0;
	if(r < tl || tr < l)
		return 0;
	if(l <= tl && tr <= r)
		return t0[v];
	int tm = (tl + tr) / 2;
	return (q0(2  * v,tl,tm,l,r) + q0(2 * v + 1,tm + 1,tr,l,r)) % p;
}
void u1(int v,int tl,int tr,int it,int ii)
{
	if(tl == tr && tl == it)
	{
		t1[v] = dp[ii];
		return;
	}
	if(it < tl || tr < it)
		return;
	int tm = (tr + tl) / 2;
	u1(2 * v,tl,tm,it,ii);
	u1(2 * v + 1,tm + 1,tr,it,ii);
	t1[v] = t1[2 * v] + t1[2 * v + 1];
	t1[v] %= p;
}
long long q1(int v,int tl,int tr,int l,int r)
{
	if(r < l)
		return 0;
	if(r < tl || tr < l)
		return 0;
	if(l <= tl && tr <= r)
		return t1[v];
	int tm = (tl + tr) / 2;
	return (q1(2  * v,tl,tm,l,r) + q1(2 * v + 1,tm + 1,tr,l,r)) % p;
}

int bs(long long k)
{
	int l,r,mid,ans;
	ans = -1;
	l = 0;r = n;
	while(l <= r)
	{
		mid = (r + l) / 2;
		if(pr[mid].first <= k)
		{
			ans = mid;
			l = mid + 1;
		}
		else
			r = mid - 1;
	}
	return ans;
}

int main()
{
ios_base::sync_with_stdio(0);
cin.tie(0);
cin>>n;
for(int i=1;i<=n;i++)
{
	cin>>a[i];
	pre[i] = pre[i - 1] + a[i];
	pre[i] %= p;
	pr[i] = {pre[i],i};
}
pr[0] = {0,0};
sort(pr,pr + n + 1);
for(int i=0;i<=n;i++)
	iii[pr[i].second] = i;
	
dp[0] = 1;
u0(1,0,n,0,0);

for(int i=1;i<=n;i++)
{
	ite = bs(pre[i]);
	if(pre[i] % 2 == 0)
	{
		dp[i] = q0(1,0,n,0,ite) + q1(1,0,n,ite + 1,n);
		dp[i] %= p;
		//cout<<i<<" "<<ite<<" "<<q0(1,0,n,0,ite)<<" "<<q1(1,0,n,ite + 1,n)<<endl;
		u0(1,0,n,iii[i],i);
	}
	else
	{
		dp[i] = q1(1,0,n,0,ite) + q0(1,0,n,ite + 1,n);
		dp[i] %= p;
		//cout<<i<<" "<<q1(1,0,n,0,ite)<<" "<<q0(1,0,n,ite + 1,n)<<endl;
		u1(1,0,n,iii[i],i);
	}
}



//for(int i=1;i<=n;i++)
	cout<<dp[n]<<endl;
return 0;	
}