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#include<bits/stdc++.h>

#define st first
#define nd second
#define pb(x) push_back(x)
#define pp(x) pop_back(x)
#define mp(a, b) make_pair(a, b)
#define all(x) (x).begin(), (x).end()
#define rev(x) reverse(all(x))
#define sor(x) sort(all(x))
#define sz(x) (int)(x).size()
#define rsz(x) resize(x)

using namespace std;

typedef long long ll;
typedef long double ld;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;
typedef vector<int> vi;
typedef vector<pii > vii;
typedef vector<ll> vl;
typedef vector<pll> vll;
typedef string str;
#define BOOST ios_base::sync_with_stdio(false);cin.tie(NULL);cout.tie(NULL);

const int mx_N = 1e5*3+10;
const ll md = 1e9+7;
const int p2 = 1<<19;
map<ll,ll>M;//reszta -> nr reszty
ll pre[mx_N];
ll pre2[mx_N];
ll tre[2][2*p2 +10];

ll suma(ll a, ll b,int typ)
{
    ll sum = 0;
    a+=p2;
    b+=p2;
    a--;
    b++;
    while(a/2 != b/2)
    {
        if(a%2 == 0)
            sum+=tre[typ][a+1];
        if(b%2 == 1)
            sum+=tre[typ][b-1];
        a>>=1;
        b>>=1;
    }
    return sum%md;
}
void dodaj(ll ind, int typ, ll val )
{
    ind+=p2;
    tre[typ][ind] = (tre[typ][ind]+val)%md;
    ind>>=1;
    while(ind > 0)
    {
        tre[typ][ind] = (tre[typ][ind<<1] +tre[typ][(ind<<1) + 1])%md;
        ind>>=1;
    }

}
void nowy(ll a)
{
    int typ = a%2;
    int ind = M[a];
    ll addit = (suma(0 , ind , typ) + suma(ind+1 , p2-1 , 1-typ))%md;
    dodaj(ind , typ, addit);
}


int main()
{
    BOOST
    int n;
    cin>>n;
    ll temp;
    for(int i = 1  ; i <= n ;  i++)
    {
        cin>>pre[i];
        pre[i] = (pre[i]+pre[i-1])%md;
        pre2[i] = pre[i];
    }
    sort(pre2+1,pre2+n+1);
    M[pre2[1]] = 0;
    ll ind = 1;
    for(int i = 2 ; i <= n ; i++)
    {
        if(pre2[i] != pre2[i-1])
        {
            M[pre2[i]] = ind;
            ind++;
        }
    }
    dodaj(0 , 0 , 1);
    for(int i = 1 ; i <= n ; i++)
    {
        nowy(pre[i]);
    }
    cout<<tre[pre[n]%2][M[pre[n]]];




    return 0;
}