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// jd
#include <bits/stdc++.h>
#define int long long
#define mp make_pair
#define pb push_back
#define ld long double
#define pii pair<int,int>
#define sz(x) (int)x.size()
#define piii pair<pii,pii>
#define precise cout<<fixed<<setprecision(10)
#define st first
#define nd second
#define ins insert
#define vi vector<int>
#define BOOST ios_base::sync_with_stdio(false);cin.tie(0);cout.tie(0)
using namespace std;
const int MAX=1<<20;
const int mod=1e9+7;
int a[MAX];
int pref[MAX];
set<int>pom;
map<int,int>conv;
int dp[MAX];
int kub(int x){
	return (x/mod)%2;
}	
int t[MAX*2][2][2];
void update(int u,int c,int ida,int idb){
	for (t[u+=MAX][ida][idb]+=c;u>1;u>>=1){
		t[u>>1][ida][idb]=(t[u][ida][idb]+t[u^1][ida][idb])%mod;
	}
}

int query(int u,int v,int ida,int idb){
	int sum=0;
	for (u+=MAX,v+=MAX+1;u<v;u>>=1,v>>=1){
		if (u&1)sum+=t[u++][ida][idb];
		if (v&1)sum+=t[--v][ida][idb];
	}
	return sum%mod;
}
const int STALA=1e6;

int32_t main(){
  BOOST;
  int n;
  cin>>n;
  pom.ins(0);
  for (int i=1;i<=n;i++)cin>>a[i],pref[i]=pref[i-1]+a[i],pom.ins(pref[i]%mod);
  int licznik=1;
  for (auto it:pom)conv[it]=licznik++;
  update(conv[0],1,0,0);
  dp[0]=1;
  // ida - kubelek , idb modulo 2
  for (int i=1;i<=n;i++){
		int modulus=pref[i]%mod;
		int kubel=kub(pref[i]);
		int wd1=conv[modulus];
		int modwa=pref[i]%2;
		dp[i]+=query(1,wd1,kubel,modwa);
		dp[i]+=query(wd1+1,STALA,kubel,modwa^1);
		dp[i]+=query(1,wd1,kubel^1,modwa^1);
		dp[i]+=query(wd1+1,STALA,kubel^1,modwa);
		dp[i]%=mod;
		update(wd1,dp[i],kubel,pref[i]%2);
  }
  cout<<dp[n];
  return 0; 
}