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#include <bits/stdc++.h>
using namespace std;
#define rep(i,a,n) for (int i=a;i<n;i++)
#define per(i,a,n) for (int i=n-1;i>=a;i--)
#define pb push_back
#define mp make_pair
#define all(x) (x).begin(),(x).end()
#define fi first
#define se second
#define SZ(x) ((int)(x).size())
typedef vector<int> VI;
typedef long long ll;
typedef pair<int,int> PII;
typedef double db;
const ll mod=1000000007;
ll powmod(ll a,ll b) {ll res=1;a%=mod; assert(b>=0); for(;b;b>>=1){if(b&1)res=res*a%mod;a=a*a%mod;}return res;}
ll gcd(ll a,ll b) { return b?gcd(b,a%b):a;}
// head

const ll N=301000;

int m;
struct fenwick {
	ll tot,c[N];
	ll query(int x) {
		ll s=0;
		for (;x;x-=x&-x) s+=c[x];
		return s;
	}
	void modify(int x,int s) {
		tot+=s;
		for (;x<=m;x+=x&-x) c[x]+=s;
	}
}c[2];

int n,a[N],s[N],dp[N];

int main() {
	scanf("%d",&n);
	rep(i,1,n+1) {
		scanf("%d",a+i);
		s[i]=(s[i-1]+a[i])%mod;
	}
	VI v;
	rep(i,0,n+1) v.pb(s[i]);
	sort(all(v));
	v.erase(unique(all(v)),v.end());
	m=SZ(v);
	rep(i,0,n+1) {
		int pos=lower_bound(all(v),s[i])-v.begin()+1;
		dp[i]=(c[1-s[i]%2].tot-c[1-s[i]%2].query(pos)+c[s[i]%2].query(pos))%mod;
		if (i==0) dp[i]=1;
		c[s[i]%2].modify(pos,dp[i]);
	}
	printf("%d\n",dp[n]);
}