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#include <iostream>
#include <vector>
#include <algorithm>
using namespace std;
typedef long long ll;
const int M = 1000000007;
const int MM = 2*M;
const int BT = 8;

struct SparseImmutablePrefixSum {
    struct Milestone{
        int idx;
        ll sum;
        bool operator<(const Milestone& ms) const {
            return idx < ms.idx;
        }
        bool operator==(const Milestone& ms) const {
            return idx == ms.idx;
        }
    };

    vector<Milestone>MS;

    void range(int a, int b, ll val) {
        MS.push_back(Milestone{.idx=a, .sum=val});
        MS.push_back(Milestone{.idx=b+1, .sum=-val});
    }
    void build() {
        MS.push_back(Milestone{.idx=0, .sum=0});
        sort(MS.begin(), MS.end());

        for(int i=1,first_of_kind=0;i<(int)MS.size();i++)
            if (MS[i].idx != MS[i-1].idx) {
                MS[i].sum += MS[first_of_kind].sum;
                first_of_kind = i;
            }
            else
                MS[first_of_kind].sum += MS[i].sum;
        
        MS.erase(unique(MS.begin(), MS.end()), MS.end());
    }

    ll get(int i) {
        return prev(upper_bound(MS.begin(), MS.end(), Milestone{.idx=i}))->sum;
    }
};

struct BlackBox{
    SparseImmutablePrefixSum even, odd;

    SparseImmutablePrefixSum& get_ps(ll val) {
        return val%2==0 ? even : odd;
    }

    void add_number(ll dp_val, int x) { //x = [0, MM)
        if (x<M) {
            get_ps(x).range(0, M-x-1, dp_val);
            get_ps(x+1).range(M-x, MM-x-1, dp_val);
            get_ps(x).range(MM-x, MM-1, dp_val);
        }
        else {
            get_ps(x+1).range(0, MM-x-1, dp_val);
            get_ps(x).range(MM-x, MM-x+M-1, dp_val);
            get_ps(x+1).range(MM-x+M, MM-1, dp_val);
        }
    }

    void build() {
        even.build();
        odd.build();
    }

    ll get(int x) {
        return get_ps(x).get(x);
    }
};

struct Block{
    int right;
    int size;
    BlackBox *bb;
};

BlackBox* make_black_box(const vector<int>& seq, const vector<ll>& dp, int from, int to) {
    BlackBox *bb = new BlackBox;
    long long acc = 0;
    for (int i=to; i >= from; i--) {
        acc = (acc + seq[i]) % MM;
        bb->add_number(dp[i-1], (int)acc);
    }
    bb->build();
    return bb;
}

int main(){
    ios::sync_with_stdio(false);
    cin.tie(nullptr);

    int n;
    cin >> n;
    vector<int>Seq(n+1);
    for (int i=1;i<=n;i++)
        cin >> Seq[i];
    
    vector<ll>Pref(n+1);
    for(int i=1;i<=n;i++)
        Pref[i] = Pref[i-1] + Seq[i];

    vector<ll>dp(n+1);
    dp[0] = 1;

    vector<Block>B;

    int last_block_end = 0;
    for (int i=1;i<=n;i++) {
        //get dp value
        ll acc = 0;
        for (int j=i;j>last_block_end;j--) {
            acc = (acc + Seq[j]) % MM;
            if ((acc%M)%2 == 0)
                dp[i] += dp[j-1];
        }
        // cerr << "B = " << B.size() << endl;
        if (!B.empty())
            for (int bi=B.size()-1;bi>=0;bi--) {
                dp[i] += B[bi].bb->get(acc);
                if(bi>0){
                    acc += Pref[B[bi].right] - Pref[B[bi-1].right];
                    acc %= MM;
                }
            }
        // cerr << "XX" << endl;

        dp[i] %= M;

        //update structure
        if (i-last_block_end < BT)
            continue;

        int bs = BT;
        while (!B.empty() && B.back().size==bs) {
            bs *= 2;
            delete B.back().bb;
            B.pop_back();
        }

        B.push_back(Block{.right=i, .size=bs, .bb=make_black_box(Seq, dp, i-bs+1, i)});
        last_block_end = i;
    }

    cout << dp[n] << "\n";

    for (Block b : B)
        delete b.bb;
    return 0;
}