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#include <iostream>
#include <stdio.h>
#include <math.h>
#include <string.h>
#include <time.h>
#include <stdlib.h>
#include <string>
#include <bitset>
#include <vector>
#include <set>
#include <map>
#include <queue>
#include <algorithm>
#include <sstream>
#include <stack>
#include <iomanip>
#include <assert.h>
using namespace std;
#define pb push_back
#define mp make_pair
typedef pair<int,int> pii;
typedef long long ll;
typedef double ld;
typedef vector<int> vi;
#define fi first
#define se second
#define fe first
#define FO(x) {freopen(#x".in","r",stdin);freopen(#x".out","w",stdout);}
#define Edg int M=0,fst[SZ],vb[SZ],nxt[SZ];void ad_de(int a,int b){++M;nxt[M]=fst[a];fst[a]=M;vb[M]=b;}void adde(int a,int b){ad_de(a,b);ad_de(b,a);}
#define Edgc int M=0,fst[SZ],vb[SZ],nxt[SZ],vc[SZ];void ad_de(int a,int b,int c){++M;nxt[M]=fst[a];fst[a]=M;vb[M]=b;vc[M]=c;}void adde(int a,int b,int c){ad_de(a,b,c);ad_de(b,a,c);}
#define es(x,e) (int e=fst[x];e;e=nxt[e])
#define esb(x,e,b) (int e=fst[x],b=vb[e];e;e=nxt[e],b=vb[e])
#define SZ 333333
const int MOD=1e9+7;
int n,a[SZ];
struct B {
ll t[SZ];
ll gs(int x) {
	ll s=0;
	for(;x>=1;x-=x&-x) (s+=t[x])%=MOD;
	return s;
}
void edt(int x,int y) {
	for(;x<SZ;x+=x&-x) (t[x]+=y)%=MOD;
}
}f[2];
ll su[SZ],so[SZ];
#define LS(x) (lower_bound(so,so+n+1,(x))-so+2)
int main()
{
	scanf("%d",&n);
	for(int i=1;i<=n;++i) scanf("%d",a+i);
	for(int i=1;i<=n;++i) su[i]=(su[i-1]+a[i])%MOD;
	for(int i=0;i<=n;++i) so[i]=su[i];
	sort(so,so+n+1);
	f[0].edt(LS(0),1);
	ll ans;
	for(int i=1;i<=n;++i) {
		int w=LS(su[i]);
		ans=f[su[i]&1].gs(w)
		+f[!(su[i]&1)].gs(SZ-1)
		-f[!(su[i]&1)].gs(w);
		ans=(ans%MOD+MOD)%MOD;
		f[su[i]&1].edt(w,ans);
	}
	printf("%d\n",int(ans));
}