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#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
#define pb push_back
#define mp make_pair
#define all(a) begin(a),end(a)
#define FOR(x,val,to) for(int x=(val);x<int((to));++x)
#define FORE(x,val,to) for(auto x=(val);x<=(to);++x)
#define FORR(x,arr) for(auto &x: arr)
#define FORS(x,plus,arr) for(auto x = begin(arr)+(plus); x != end(arr); ++x)
#define FORREV(x,plus,arr) for(auto x = (arr).rbegin()+(plus); x !=(arr).rend(); ++x)
#define REE(s_) {cout<<s_<<'\n';exit(0);}
#define GET(arr) for(auto &i: (arr)) sc(i)
#define whatis(x) cerr << #x << " is " << (x) << endl;
#define e1 first
#define e2 second
#define INF 0x7f7f7f7f
typedef std::pair<int,int> pi;
typedef std::vector<int> vi;
typedef std::vector<std::string> vs;
typedef int64_t ll;
typedef uint64_t ull;
#define umap unordered_map
#define uset unordered_set
using namespace std;
using namespace __gnu_pbds;

#ifdef ONLINE_JUDGE
#define whatis(x) ;
#endif
#ifdef _WIN32
#define getchar_unlocked() _getchar_nolock()
#define _CRT_DISABLE_PERFCRIT_LOCKS
#endif
template<class L, class R> ostream& operator<<(ostream &os, map<L, R> P) { for(auto const &vv: P)os<<"("<<vv.first<<","<<vv.second<<")"; return os; }
template<class T> ostream& operator<<(ostream &os, set<T> V) { os<<"[";for(auto const &vv:V)os<<vv<<","; os<<"]"; return os; }
template<class T> ostream& operator<<(ostream &os, vector<T> V) { os<<"[";for(auto const &vv:V)os<<vv<<","; os<<"]"; return os; }
template<class L, class R> ostream& operator<<(ostream &os, pair<L, R> P) { os<<"("<<P.first<<","<<P.second<<")"; return os; }
inline int fstoi(const string &str){auto it=str.begin();bool neg=0;int num=0;if(*it=='-')neg=1;else num=*it-'0';++it;while(it<str.end()) num=num*10+(*it++-'0');if(neg)num*=-1;return num;}
inline void getch(char &x){while(x = getchar_unlocked(), x < 33){;}}
inline void getstr(string &str){str.clear(); char cur;while(cur=getchar_unlocked(),cur<33){;}while(cur>32){str+=cur;cur=getchar_unlocked();}}
template<typename T> inline bool sc(T &num){ bool neg=0; int c; num=0; while(c=getchar_unlocked(),c<33){if(c == EOF) return false;} if(c=='-'){ neg=1; c=getchar_unlocked(); } for(;c>47;c=getchar_unlocked()) num=num*10+c-48; if(neg) num*=-1; return true;}template<typename T, typename ...Args> inline void sc(T &num, Args &...args){ bool neg=0; int c; num=0; while(c=getchar_unlocked(),c<33){;} if(c=='-'){ neg=1; c=getchar_unlocked(); } for(;c>47;c=getchar_unlocked()) num=num*10+c-48; if(neg) num*=-1; sc(args...); }
template<typename T> using ordered_set = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>; //s.find_by_order(), s.order_of_key() <- works like lower_bound
template<typename T> using ordered_map = tree<T, int, less<T>, rb_tree_tag, tree_order_statistics_node_update>;
#define N 300003

constexpr int mod = 1e9 + 7;
#define int ll
/* ll t[N + 1]; */
/* ll t[2][N + 1]; */
int t[2][N + 1];

//1 INDEXED, increment in function if needed

template<int ind>
inline void upd(int pos, int val){ //val is delta
    ++pos;
    for(;pos <= N;pos += pos & (-pos)){
        t[ind][pos] += val;
        t[ind][pos] %= mod;
        /* if(t[ind][pos] >= mod) */
        /*     t[ind][pos] -= mod; */
    }
}

template<int ind>
inline int query(int r){ //[0,r]
    ++r;
    int ret = 0;
    for(;r > 0;r -= r & (-r)){
        ret += t[ind][r];
        ret %= mod;
        /* if(ret >= mod) */
        /*     ret -= mod; */
    }
    return ret;
}

/* int main(){ */
int32_t main(){
    ios_base::sync_with_stdio(0);cin.tie(0);
    /* FOR(i,1,100){ */
    /*     /1* FOR(x,1,100){ *1/ */
    /*     FOR(x,1,i){ */
    /*         int orig = (i - x) / mod; */
    /*         int nw = i / mod - x / mod - (i % mod - x % mod < 0); */
    /*         cout << i << ' ' << x << ": " << orig << ' ' << nw << '\n'; */
    /*         assert(orig == nw); */
    /*     } */
    /* } */
    int n;
    sc(n);
    ++n;
    /* int a[n+1]; */
    int a[n];
    a[0] = 0;
    FOR(i,1,n)
        sc(a[i]);
    /* GET(a); */
    ll pre[n];
    pre[0] = a[0];
    vector<ll> vec{0, a[0]};
    FOR(i,1,n){
        pre[i] = pre[i - 1] + a[i];
        // nie chcę % mod, bo w końcu dzielę przez mod też.
        /* if(pre[i] >= mod) */
        /*     pre[i] -= mod; */
        /* vec.push_back(pre[i]); */
        // tutaj chcę % mod
        vec.push_back(pre[i] % mod);
    }
    sort(all(vec));
    vec.erase(unique(all(vec)),vec.end());
    int preord[n];
    FOR(i,0,n){
        // do the lower_bound opt obv xdd
        /* preord[i] = lower_bound(all(vec), pre[i]) - vec.begin(); */
        preord[i] = lower_bound(all(vec), pre[i] % mod) - vec.begin();
    }
    ll dp[n];
    dp[0] = 1;
    upd<0>(0, 1);
    FOR(i,1,n){
        dp[i] = 0;
        /* ll prmod = pre[i] % mod; */
        /* FOR(x,0,i){ */
        /*     if((pre[i] - pre[x]) % mod % 2 == 0){ */
        /*         dp[i] += dp[x]; */
        /*     } */
        /* } */
        ll fixdown = (pre[i] & 1) + ((pre[i] / mod) & 1);
        if(fixdown % 2 == 0){
            /* dp[i] += query<1>(300001) - (preord[i] > 0 ? query<1>(preord[i] - 1) : 0); */
            dp[i] += query<1>(300001) - query<1>(preord[i]); // preord[x] > preord[i]
            dp[i] += query<0>(preord[i]); // pre[i] % mod >= pre[x] % mod, czyli 0 + 0 + 0.
            /* upd<0>(prmod, dp[i]); */
            dp[i] %= mod;
            upd<0>(preord[i], dp[i]);
        }
        else{
            dp[i] += query<0>(300001) - query<0>(preord[i]);
            dp[i] += query<1>(preord[i]);
            dp[i] %= mod;
            upd<1>(preord[i], dp[i]);
        }
        /* FOR(x,0,i){ */
        /*     ll fixdoth = (pre[x] & 1) - ((pre[x] / mod) & 1); */
        /*     ll sth = fixdown + fixdoth - (pre[i] % mod < pre[x] % mod); */
        /*     if(sth % 2 == 0) */
        /*         dp[i] += dp[x]; */
        /* } */
    }
    dp[n - 1] += mod;
    dp[n - 1] %= mod;
    cout << dp[n - 1] << '\n';
}