#include<iostream>

 #include<cstdio>

 #include<cstring>

 #include<algorithm>

 using namespace std;

 typedef long long ll;

 const int mod=,N=;

 int gi(){

     int str=,f=;char ch=getchar();

     while(ch>'' || ch<''){if(ch=='-')f=-;ch=getchar();}

     while(ch>='' && ch<='')str=str*+ch-,ch=getchar();

     return str*f;

 }

 int a[N],id[N],n;ll Tree[N*],sum[N],b[N],f[N];

 int pf(ll x)

 {

     int l=,r=n,mid;

     while(l<=r)

     {

         mid=(l+r)>>;

         if(b[mid]==x)return mid;

         if(x>b[mid])l=mid+;

         else r=mid-;

     }

     return ;

 }

 void add(int sta,ll x){for(int i=sta;i<=n;i+=(i&(-i)))Tree[i]+=x,Tree[i]%=mod;}

 ll getsum(int sta)

 {

     ll sum=;

     for(int i=sta;i>=;i-=(i&(-i)))sum+=Tree[i],sum%=mod;

     return sum;

 }

 int main()

 {

     n=gi();

     for(int i=;i<=n;i++)a[i]=gi(),sum[i]=sum[i-]+a[i],b[i]=sum[i];

     sort(b+,b+n+);

     for(int i=;i<=n;i++)

     {

         id[i]=pf(sum[i]);

     }

     for(int i=;i<=n;i++)

     {

         f[i]=getsum(id[i]);

         if(sum[i]>=)f[i]++;

         f[i]%=mod;

         add(id[i],f[i]);

     }

     printf("%lld",f[n]%mod);

     return ;

 }