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#include<bits/stdc++.h>
#define fi first
#define se second
using namespace std;
const int N=3e5;
const int PP=6e5;
const int MOD=1e9+7;
int tab[N+10];
int p[N+10];
map<int,int> c[2];
int dp[N+10];
int pot;
int tree[2][2*PP+10];
int read(int tt,int l,int r)
{
	int ans=0;
	for(l+=pot-1,r+=pot-1;l<=r;l/=2,r/=2)
	{
		if(l%2==1)
			ans=(ans+tree[tt][l++])%MOD;
		if(r%2==0)
			ans=(ans+tree[tt][r--])%MOD;
	}
	return ans;
}
void add(int tt,int g,int val)
{
	for(g+=pot-1;g>0;g/=2)
		tree[tt][g]=(tree[tt][g]+val)%MOD;
	return;
}
int main()
{
	ios_base::sync_with_stdio(false);
	cin.tie(NULL);
	cout.tie(NULL);
	int n;
	cin>>n;
	for(pot=1;pot<n;pot*=2);
	for(int i=1;i<=n;i++)
	{
		cin>>tab[i];
		p[i]=(tab[i]+p[i-1])%MOD;
		c[p[i]%2][p[i]]=0;
	}
	c[0][0]=c[1][0]=c[0][MOD]=c[1][MOD]=0;
	for(int j:{0,1})
	{
		int i=0;
		for(auto v:c[j])
			c[j][v.fi]=++i;
	}
	dp[0]=1;
	add(p[0]%2,c[p[0]%2][p[0]],1);
	for(int i=1;i<=n;i++)
	{
		dp[i]=(read(p[i]%2,1,c[p[i]%2][p[i]])
				+read((p[i]+1)%2,c[(p[i]+1)%2].upper_bound(p[i])->se,pot))%MOD;
		add(p[i]%2,c[p[i]%2][p[i]],dp[i]);
		//cerr<<i<<" "<<mp[i]<<" "<<dp[i]<<"\n";
	}
	cout<<dp[n]<<"\n";
	return 0;
}