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#include <bits/stdc++.h>

using namespace std;

const int maxn = 300000 + 7;
const int q = 1e9 + 7;

typedef long long ll;

template <typename T,typename U>
std::pair<T,U> operator+(const std::pair<T,U> & l,const std::pair<T,U> & r) {   
    return {l.first+r.first,l.second+r.second};                                    
}

/*struct node{
    ll prefix;
    ll wynik;
};*/

pair<ll,ll> tree[maxn*2];
int n;

void build(pair<ll,int> tab[]) {
    for(int i=0;i<n;i++) {
        /*if(tab[i].first%2 == 0) {
            tree[n+i].first = tab[i].first;
            tree[n+i].second = 0;
        }
        else {
            tree[n+i].second = tab[i].first;
            tree[n+i].first = 0;
        }*/
        tree[n+i].first = 0;
        tree[n+i].second = 0;
    }
    for(int i=n-1;i>0;i--) {
        tree[i] = tree[2*i] + tree[2*i | 1];
    }
}

void update(int p,int value, bool nieparz) {
    if(!nieparz) {
        tree[p+n].first = value;
    }
    else {
        tree[p+n].second = value;
    }
    
    p = p+n;

    for(int i=p;i>1;i/=2) {
        tree[i/2] = tree[i] + tree[i^1];
    }
}

//daje sume ale bez r
ll query(int l,int r, bool nieparz) {
    //cout<<"query: "<<l<<' '<<r<<' '<<nieparz<<" wyn: ";
    ll wyn = 0;
    for(l += n, r += n;l < r; l/=2 , r/=2) {
        if(l&1) {
            if(!nieparz)
                wyn += tree[l++].first;
            else
                wyn += tree[l++].second;
            wyn %= q;
        }
        if(r&1) {
            if(!nieparz)
                wyn += tree[--r].first;
            else
                wyn += tree[--r].second;
            wyn %= q;
        }
    }
    //cout<<wyn<<'\n';
    return wyn;
}

void wypisz(int x) {
    cout<<'\n';
    cout<<"=========================\n";
    for(int i=1;i<2*n;i++) {
        if(i == n) 
            cout<<'\n';
        if(i == x+n)
            cout<<"  ";
        cout<<"{ "<<tree[i].first<<", "<<tree[i].second<<" } \n";
        
    }
    cout<<"=========================\n";
    cout<<'\n';
    /*int ile = n, gleb = n;
    while(ile > 0) {
        for(int i=0;i<n;i++) {
            cout<<"{ "<<tree[gleb+i].first<<", "<<tree[gleb+i].second<<" } , ";
        }
        ile /= 2;
    }*/
}


int main() {
    ios_base::sync_with_stdio(0);
    cin.tie(0);

    cin>>n;
    int tab[n];
    for(int i=0;i<n;i++) {
        cin>>tab[i];
    }
    n++;
    pair<ll,int> suma_prefix[n];
    //suma_prefix[0] = {tab[0],0};
    ll suma = 0;
    for(int i=0;i<n;i++) {
        suma_prefix[i] = {suma,i};
        if(i==n-1)break;
        suma += tab[i];
        suma %= q;
    }
    sort(suma_prefix,suma_prefix+n);
    int index[n];
    for(int i=0;i<n;i++) {
        index[suma_prefix[i].second] = i;
    }
    
    /*for(int i=0;i<n;i++) {
        cout<<i<<": suma: "<<suma_prefix[i].first<<" index: "<<suma_prefix[i].second<<'\n';
    }*/
    /*ll wyn[n+1];
    fill_n(wyn+1,n,0);
    wyn[0] = 1;*/
    ll wyn = 0;
    for(int i=0;i<n;i++) {
        //wypisz(index[i]);
        if(i==0) {
            update(index[0],1,0);
            continue;
        }
        if(suma_prefix[index[i]].first%2==0) {
            //update(i,wyn[i]);
            wyn = query(0,index[i]+1,0);
            wyn += query(index[i]+1,n,1);
            wyn %= q;
        }
        else {
            wyn = query(0,index[i]+1,1);
            wyn += query(index[i]+1,n,0);
            wyn %= q;
            //update(i,wyn[i]);
        }
        bool nieparz = false;
        if(suma_prefix[index[i]].first%2 == 1)nieparz = true;
        update(index[i],wyn,nieparz);
        //cout<<wyn<<'\n';
    }
    cout<<wyn<<'\n';
    //cout<<wyn[n]<<'\n';
}