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

typedef long long LL;
typedef long double LD;
typedef pair<int, int> PII;
typedef pair<LL, LL> PLL;

#define all(x) (x).begin(), (x).end()
#define sz(x) (int)(x).size()

template<typename _T> inline void _DBG(const char *s, _T x) { cerr << s << " = " << x << "\n"; }
template<typename _T, typename... args> void _DBG(const char *s, _T x, args... a) { while(*s != ',') cerr << *s++; cerr << " = " << x << ','; _DBG(s + 1, a...); }

#ifdef LOCAL
#define _upgrade ios_base::sync_with_stdio(0);
#define DBG(...) _DBG(#__VA_ARGS__, __VA_ARGS__)
#else
#define _upgrade ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
#define DBG(...) (__VA_ARGS__)
#define cerr if(0) cout
#endif

// ********************** CODE ********************** //

const int N = 3e5 + 7;
const int S = 500;
const int M = 1e9 + 7;

int n;
LL A[N], dp[N];

struct block {
    LL offset;
    LL dp_sum[2];
    vector<pair<LL, int>> v;
};

inline LL addM(LL a, LL b)
{
    return (a + b < M ? a + b : a + b - M);
}

inline LL subM(LL a, LL b)
{
    return (a - b >= 0 ? a - b : a - b + M);
}

inline LL get_val(block *b, int i)
{
    return b->offset + b->v[i].first;
}

pair<block*, block*> split(block *b, LL x)
{
    int id = sz(b->v) - 1;
    while (id >= 0 && get_val(b, id) < x)
        id--;

    block *r = new block();
    r->offset = b->offset;
    r->dp_sum[0] = r->dp_sum[1] = 0;
    for (int i = id + 1; i < sz(b->v); i++)
    {
        r->v.push_back(b->v[i]);
        bool bv = b->v[i].first % 2;
        r->dp_sum[bv] = addM(r->dp_sum[bv], dp[b->v[i].second]);
        b->dp_sum[bv] = subM(b->dp_sum[bv], dp[b->v[i].second]);
    }
    b->v.resize(id + 1);

    return {b, r};
}

void merge(block *l, block *r)
{
    for (int i = 0; i < sz(r->v); i++)
    {
        l->v.push_back({get_val(r, i) - l->offset, r->v[i].second});
        bool b = (get_val(r, i) - l->offset) % 2;
        l->dp_sum[b] = addM(l->dp_sum[b], dp[l->v.back().second]);
    }

    delete r;
}

void recalc(vector<block*> &new_blocks, vector<block*> &blocks, int x, int i, int j)
{
    auto [l, r] = split(blocks[j], M - x);
    
    r->offset += x;
    new_blocks.push_back(r);
    
    for (int k = j + 1; k < sz(blocks); k++)
    {
        while (k < sz(blocks) && sz(new_blocks.back()->v) + sz(blocks[k]->v) <= S)
        {
            blocks[k]->offset += x;
            merge(new_blocks.back(), blocks[k]);
            k++;
        }
        if (k < sz(blocks))
        {
            blocks[k]->offset += x;
            new_blocks.push_back(blocks[k]);
        }
    }

    if (sz(new_blocks.back()->v) + 1 <= S)
    {
        new_blocks.back()->v.push_back({x - new_blocks.back()->offset, i - 1});
        bool b = (x - new_blocks.back()->offset) % 2;
        new_blocks.back()->dp_sum[b] = addM(new_blocks.back()->dp_sum[b], dp[i - 1]);
    }
    else
    {
        block *bx = new block();
        bx->offset = 0;
        bx->dp_sum[0] = bx->dp_sum[1] = 0;
        bx->v.push_back({x, i - 1});
        bx->dp_sum[x % 2] = dp[i - 1];
        new_blocks.push_back(bx);
    }

    for (int k = 0; k < j; k++)
    {
        while (k < j && sz(new_blocks.back()->v) + sz(blocks[k]->v) <= S)
        {
            blocks[k]->offset += x - M;
            merge(new_blocks.back(), blocks[k]);
            k++;
        }
        if (k < j)
        {
            blocks[k]->offset += x - M;
            new_blocks.push_back(blocks[k]);    
        }
    }

    l->offset += x - M;
    
    if (sz(new_blocks.back()->v) + sz(l->v) <= S)
        merge(new_blocks.back(), l);
    else
        new_blocks.push_back(l);
}

int main()
{
    _upgrade

    cin >> n;
    for (int i = 1; i <= n; i++)
        cin >> A[i];

    vector<block*> blocks;

    dp[0] = 1;
    for (int i = 1; i <= n; i++)
    {
        LL x = A[i];

        if (i == 1)
        {
            block *bx = new block();
            bx->offset = 0;
            bx->dp_sum[0] = bx->dp_sum[1] = 0;
            bx->v.push_back({x, i - 1});
            bx->dp_sum[x % 2] = dp[i - 1];
            blocks.push_back(bx);

            for (auto &b: blocks)
                dp[i] = addM(dp[i], b->dp_sum[(bool)(b->offset % 2)]);

            continue;
        }

        vector<block*> new_blocks;
        for (int j = sz(blocks) - 1; j >= -1; j--)
        {
            if (j == -1)
            {
                recalc(new_blocks, blocks, x, i, 0);
                break;
            }

            LL mx = get_val(blocks[j], 0);
            if (M - x <= mx)
            {
                recalc(new_blocks, blocks, x, i, j);
                break;
            }
        }

        swap(blocks, new_blocks);
        for (auto &b: blocks)
            dp[i] = addM(dp[i], b->dp_sum[(bool)(b->offset % 2)]);
    }

    cout << dp[n] << "\n";
    return 0;
}