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#include <cstdio>
#include <cstring>
#include <cmath>
#include <cassert>
#include <iostream>
#include <algorithm>
#include <iterator>
#include <string>
#include <vector>
#include <queue>
#include <bitset>
#include <utility>
#include <stack>

using namespace std;
typedef long long LL;
typedef pair<int,int> PII;
typedef vector<int> VI;
#define MP make_pair
#define FOR(v,p,k) for(int v=(p);v<=(k);++v)
#define FORD(v,p,k) for(int v=(p);v>=(k);--v)
#define REP(i,n) for(int i=0;i<(n);++i)
#define VAR(v,i) __typeof(i) v=(i)
#define FOREACH(i,c) for(VAR(i,(c).begin());i!=(c).end();++i)
#define PB push_back
#define ST first
#define ND second
#define SIZE(x) (int)x.size()
#define ALL(c) c.begin(),c.end()

#define ODD(x) ((x)%2)
#define EVEN(x) (!(ODD(x)))


const int P = 1000000007;
int main() {
    int n;
    scanf("%d\n", &n);
    VI a;
    a.reserve(n);
    int mx = 0;
    REP(i, n) {
        int aa;
        scanf("%d", &aa);
        mx = max(mx, aa);
        a.PB(aa);
    }
    int res = 0;
    if (mx <= (P - 1) / n) {
        VI dp(2);
        REP(i, n) {
            if (a[i] % 2) {
                swap(dp[0], dp[1]);
            } else {
                dp[0] *= 2;
                dp[0] %= P;
            }
        }
        res = dp[0];
    } else {
        vector<LL> pref_sums(n);
        LL cumsum = 0;
        REP(i, n) {
            cumsum += a[i];
            pref_sums[i] = cumsum;
        }
        
        vector<VI> dp(n, VI(2));
        dp[0][a[0] % 2] = 1;

        //printf("dp[%d]=%d %d\n", 0, dp[0][0], dp[0][1]);
        FOR(i, 1, n-1) {
            int d = (pref_sums[i] % P) % 2;
            dp[i][d] = 1;
            REP(j, i) {
                int diff = (((pref_sums[i] - pref_sums[j]) % P) % 2);
                int prev0 = dp[j][0];
                dp[i][diff] += prev0;
                dp[i][diff] %= P;
            }
            //printf("dp[%d]=%d %d\n", i, dp[i][0], dp[i][1]);
        }
        res = dp[n-1][0];

    }


    printf("%d\n", res);
    return 0;
}