#include <bits/stdc++.h>
#define mp make_pair
#define fi first
#define se second
#define pb push_back
#define bit(n) (1LL << (n))
#define getbit(x, i) (((x) >> (i)) & 1)
#define pii pair<int, int>
#define ALL(x) (x).begin(), (x).end()
#define sz(x) ((int) (x).size())
using namespace std;
const int M = 5e5 + 5;
const int mod = 1e9 + 7;
const int oo = 1e9;
const long long ooo = 1e18;
const double pi = acos(-1);

template<typename T1, typename T2> bool mini(T1 &a, T2 b) {if(a > b) a = b; else return 0; return 1;}
template<typename T1, typename T2> bool maxi(T1 &a, T2 b) {if(a < b) a = b; else return 0; return 1;}

mt19937_64 rd(chrono::steady_clock::now().time_since_epoch().count());

typedef long long ll;
typedef unsigned long long ull;

int main() {
    ios_base::sync_with_stdio(0); cin.tie(0);
    #ifdef LOCAL
    freopen("file.inp", "r",stdin);
    #endif
    int n; cin >> n;
    vector<int> a(n);
    for (int &x : a) {
        cin >> x;
        x++;
    }

    vector<vector<int>> cand(n);
    vector<int> dp(n + 1);
    
    const int N = 2e6 + 5;

    vector<int> cnt(N, 0);
    vector<ull> hasher(N, 0), sum(N, 0);

    for (int i = 1; i < N; i++) {
        hasher[i] = rd();
        sum[i] = hasher[i] + sum[i - 1];
    }

    auto getsum = [&](int l, int r) -> ull {
        return sum[r] - sum[l - 1];
    };


    function<void(int, int)> solve = [&](int l, int r) -> void {
        if (l == r) {
            cand[r].push_back(r + 1);
            return;
        }

        int mid = (l + r) >> 1;
        int mx = -oo, mn = oo;
        
        vector<int> vis;
        set<pair<ull, int>> posl, posr;
        ull cur = 0;

        // cerr << l << " " << r << " " << mid << "\n";

        for (int i = mid; i >= l; i--) {    
            maxi(mx, a[i]);
            mini(mn, a[i]);

            vis.push_back(a[i]);
            cnt[a[i]]++;
            cur += hasher[a[i]];
            maxi(mx, a[i]);
            
            int j = a[i];
            while (cnt[j] > 1) {
                if (j == mn) {
                    mn++;
                    maxi(mx, mn);
                }

                cnt[j] = 0;
                cur -= 2 * hasher[j];
                
                cnt[j + 1]++;
                cur += hasher[j + 1];

                vis.push_back(j + 1);
                
                j++;
            }

            // cerr << "at " << i << ": " << cur << " " << getsum(mn, mx) - cur + hasher[mn] <<  " " << mn << " " << mx << "\n";

            ull rev = getsum(mn, mx) - cur + hasher[mn];
            posl.insert({cur, i});
            posr.insert({rev, i});
        }

        for (int x : vis) {
            cnt[x] = 0;
        }
        vis.clear();
        mn = oo, mx = -oo;
        cur = 0;

        for (int i = mid + 1; i <= r; i++) {    
            maxi(mx, a[i]);
            mini(mn, a[i]);

            vis.push_back(a[i]);
            cnt[a[i]]++;
            cur += hasher[a[i]];
            maxi(mx, a[i]);
            
            int j = a[i];
            while (cnt[j] > 1) {
                if (j == mn) {
                    mn++;
                    maxi(mx, mn);
                }

                cnt[j] = 0;
                cur -= 2 * hasher[j];
                
                cnt[j + 1]++;
                cur += hasher[j + 1];

                vis.push_back(j + 1);
                
                j++;
            }

            // cerr << "at " << i << ": " << cur << " " << getsum(mn, mx) - cur + hasher[mn] <<  " " << mn << " " << mx << "\n";

            for (auto it = posr.lower_bound({cur, -oo}); it != posr.end() && it->fi == cur; it++) {
                cand[it->se].push_back(i + 1);
            }

            ull rev = getsum(mn, mx) - cur + hasher[mn];
            
            if (mn < mx) {
                for (auto it = posl.lower_bound({rev, -oo}); it != posl.end() && it->fi == rev; it++) {
                    cand[it->se].push_back(i + 1);
                }
            }
        }

        for (int x : vis) {
            cnt[x] = 0;
        }

        solve(l, mid);
        solve(mid + 1, r);
    };

    solve(0, n - 1);


    auto add = [&](int &a, int b) -> void {
        a += b;
        if (a >= mod)
            a -= mod;
    };

    dp[0] = 1;
    for (int i = 0; i < n; i++) {
        for (int j : cand[i]) {
            // cerr << i << " " << j - 1 << "\n";
            add(dp[j], dp[i]);
        }
    }

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

    return 0;
}