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#include <bits/stdc++.h>
using namespace std;

int n;
long long p=10e8+7;
struct maciek{long long r; int ind; int scal;};
maciek pref[300200];
bool skal[300200];

bool majonez1(maciek A, maciek B)
{
    return A.r<B.r;
}

bool majonez2(maciek A, maciek B)
{
    return A.ind<B.ind;
}

const int baza=1<<19;
long long d0[baza * 2];

void update0(int poz, long long war) {
while(poz > 0) {
    d0[poz] =(d0[poz]+ war)%p;
    poz /= 2;
}
return;
}

long long czytaj0(int targetleft, int targetright, int currentleft, int currentright, int poz) {
if(targetleft <= currentleft && currentright <= targetright) {
    return d0[poz];
}
long long wyn = 0;
if(targetleft <= (currentleft + currentright) / 2) {
    wyn =(wyn+ czytaj0(targetleft, targetright, currentleft, (currentleft + currentright) / 2, poz * 2))%p;
}
if((currentleft + currentright) / 2 < targetright) {
    wyn =(wyn+ czytaj0(targetleft, targetright, (currentleft + currentright) / 2 + 1, currentright, poz * 2 + 1))%p;
}
return wyn;
}

long long d1[baza * 2];

void update1(int poz, long long war) {
while(poz > 0) {
    d1[poz] += war;
    d1[poz]=d1[poz]%p;
    poz /= 2;
}
return;
}

long long czytaj1(int targetleft, int targetright, int currentleft, int currentright, int poz) {
if(targetleft <= currentleft && currentright <= targetright) {
    return d1[poz];
}
long long wyn = 0;
if(targetleft <= (currentleft + currentright) / 2) {
    wyn =(wyn+ czytaj1(targetleft, targetright, currentleft, (currentleft + currentright) / 2, poz * 2))%p;
}
if((currentleft + currentright) / 2 < targetright) {
    wyn =(wyn+ czytaj1(targetleft, targetright, (currentleft + currentright) / 2 + 1, currentright, poz * 2 + 1))%p;
}
return wyn;
}


int main()
{
    ios_base::sync_with_stdio(0);
    cin>>n;
    for(int i=1;i<=n;i++)
    {
        long long a;
        cin>>a;
        pref[i].r=(pref[i-1].r+a)%p;
        pref[i].ind=i;
    }

    sort(pref, pref+n+1, majonez1);

    int l=0;
    for(int i=0;i<=n;i++)
    {
        if(skal[i]==0)
        {
            skal[i]=1;
            pref[i].scal=l;
            int x=i;
            while(pref[x+1].r==pref[i].r&&x<n)
            {
                pref[x+1].scal=l;
                skal[x+1]=1;
                x++;
            }
            l++;
        }
    }

    sort(pref,pref+n+1,majonez2);

   // for(int i=0;i<=n;i++)cout<<pref[i].r<<" "<<pref[i].scal<<endl;
   update0(baza,1);
   for(int i=1;i<n;i++)
   {
       if(pref[i].r%2==0)
       {
           long long b=0;
            long long a=czytaj0(baza,baza+pref[i].scal,baza,2*baza-1,1);
            if(pref[i].scal<n)b=czytaj1(baza+pref[i].scal+1,baza+n,baza,baza*2-1,1);
            long long dp=(a+b)%p;
            update0(baza+pref[i].scal,dp);
       }
       else
       {
            long long b=0;
            long long a=czytaj1(baza,baza+pref[i].scal,baza,2*baza-1,1);
            if(pref[i].scal<n)b=czytaj0(baza+pref[i].scal+1,baza+n,baza,baza*2-1,1);
            long long dp=(a+b)%p;
            update1(baza+pref[i].scal,dp);
       }
   }

    if(pref[n].r%2==0)
    {
        long long b=0;
        long long a=czytaj0(baza,baza+pref[n].scal,baza,2*baza-1,1);
        if(pref[n].scal<n)b=czytaj1(baza+pref[n].scal+1,baza+n,baza,baza*2-1,1);
        long long dp=(a+b)%p;
        cout<<dp;
       }
    else
    {
        long long b=0;
        long long a=czytaj1(baza,baza+pref[n].scal,baza,2*baza-1,1);
        if(pref[n].scal<n)b=czytaj0(baza+pref[n].scal+1,baza+n,baza,baza*2-1,1);
        long long dp=(a+b)%p;
        cout<<dp;
    }

}