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#include <cstdio>
#include <vector>
#include <algorithm>

const int MOD = 1000000007;

struct CountTree {
    long long int *el, s;

    CountTree(int size) {
        el = new long long int[2 * (s = 1 << size)];
        for (int x = 0; x < 2 * s; ++x) {
            el[x] = 0;
        }
    }

    ~CountTree() {
        delete[]el;
    }

    void Set(int p, int v) {
        for (p += s; p; p >>= 1) {
            el[p] += v;
        }
    }

    long long int Find(int p, int k) {
        long long int m = 0;
        p += s;
        k += s;
        while (p < k) {
            if (p & 1) m += el[p++];
            if (!(k & 1)) m += el[k--];
            p >>= 1;
            k >>= 1;
        }

    if (p == k) m += el[p];
    return m;
    }
};

CountTree tree_even(19);
CountTree tree_odd(19);
std::vector<int> partials;

long long int get(CountTree &tree, int lhs, int rhs) {
    int a = std::lower_bound(partials.begin(), partials.end(), lhs) - partials.begin();
    int b = std::upper_bound(partials.begin(), partials.end(), rhs) - partials.begin() - 1;

    if (a>b) {
        return 0;
    } else {
        return tree.Find(a, b) % MOD;
    }
}

void set(CountTree &tree, int key, int value) {
    int a = std::lower_bound(partials.begin(), partials.end(), key) - partials.begin();
    tree.Set(a, value);
}

int main() {
    int N;
    std::vector<int> values;

    scanf("%d", &N);

    for (int i=0; i<N; ++i) {
        int x;
        scanf("%d", &x);
        values.push_back(x);
    }

    long long int sum=0;
    std::vector<int> sums(N, 0);
    for (int i=N-1; i>=0; i--) {
        sum += values[i];
        sum %= MOD;
        partials.push_back(sum);
        sums[i] = sum;
    }

    std::sort(partials.begin(), partials.end());

    long long int total = 1;
    for (int i=0; i<N; ++i) {
        int val = values[i];
        long long int result = 0;
        int cum = sums[i];

        int lhs = cum; //0 -> cum
        int rhs = (cum+MOD-val-1); // MOD-val-1 -> (cum+MOD-val-1)%MOD

        int lhs2 = cum+MOD-val; //MOD-val
        int rhs2 = cum+MOD-1; //MOD-1

        if (val % 2 == 0) {
            result += total;
        }

        if ((val % 2 == 0) == (cum % 2 == 0)) {
            result += get(tree_even, lhs, rhs);
            if (rhs >= MOD) {
                result += get(tree_odd, 0, rhs % MOD);
            }

            result += get(tree_odd, lhs2, rhs2);
            if (rhs2 >= MOD) {
                if (lhs2 >= MOD) {
                    result += get(tree_even, lhs2%MOD, rhs2%MOD);
                } else {
                    result += get(tree_even, 0, rhs2 % MOD);
                }
            }
        } else {
            result += get(tree_odd, lhs, rhs);
            if (rhs >= MOD) {
                result += get(tree_even, 0, rhs % MOD);
            }

            result += get(tree_even, lhs2, rhs2);
            if (rhs2 >= MOD) {
                if (lhs2 >= MOD) {
                    result += get(tree_odd, lhs2%MOD, rhs2%MOD);
                } else {
                    result += get(tree_odd, 0, rhs2 % MOD);
                }
            }
        }

        if (cum % 2 == 0) {
            set(tree_even, cum, total);
        } else {
            set(tree_odd, cum, total);
        }

        total = result % MOD;
    }

    printf("%lld\n", total);
    return 0;
}