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#include <stdio.h>
#include <time.h>
#include <math.h>
#include <stdlib.h>
#include <string.h>
#include <map> 
#include <string>
#include <vector>  
#include <iostream> 
#include <sstream> 
#include <queue>
#include <algorithm>
#include <assert.h>


using namespace std;

#define ll long long
#define PB 		push_back
#define FOR(a,start,end) 	for(int a=int(start); a<int(end); a++)
#define INF 		INT_MAX
#define SORT(a) 	sort(a.begin(),a.end()) 
#define CL(a,x) 		memset(a,x,sizeof(a))
#define REP(a,x)	for(int a=0;a<x;a++)
#define REP1(a,x)	for(int a=1;a<=x;a++)
#define MP 		make_pair



typedef vector<ll>     vi;
typedef pair<ll, ll>     pii;
typedef vector<string> vs;
typedef vector<pii> vii;
typedef vector<vector<ll> > vvi;
typedef vector<vector<string> > vvs;
typedef vector<pair<string, string> > vss;
typedef pair<string, string> pss;
typedef pair<ll, pii> ppii;
typedef vector<ppii> vppii;
typedef vector<vector<pii> > vvii;
typedef vector<vvi> vvvi;


ll n, k, a, b, c, z, m, d, t;

vi vk, va, vb, vc;
vvi vva;
vii vkx;


int main() {
	//freopen("c:\\wojtek\\uva\\pa\\debug\\t1.in", "rt", stdin);


//	while (1) {
	d = 1000000007;
	z = 0;
	cin >> n;

	vk.assign(n + 1, 0);
	va.assign(n + 1, 0);
	vb.assign(n + 1, 0);

	for (int i = 1; i <= n; i++) {
		cin >> vk[i];
	}

	for (int i = 1; i <= n; i++) {
		va[i] = vk[i] + va[i - 1];
	}
	if (va[n] >= d) {

		for (int i = 1; i <= n; i++) {
			vb[i] += 1 - ((va[i] % d) % 2);
			vb[i] %= d;
			if (vb[i] > 0) {
				for (int j = i + 1; j <= n; j++) {
					if ((((va[j] - va[i]) % d) % 2) == 0) {
						vb[j] += vb[i];
						vb[j] %= d;
					}
				}
			}

		}
		z = vb[n];
	}
	else {
		a = 1;
		z = 0;
		if (va[n] % 2 == 0) {
			for (int i = 1; i <= n; i++) {
				if (va[i] % 2 == 0) {
					z = a;
					a <<= 1;
					a %= d;
				}
			}
		}

	}

	cout << z << endl;
	//	}

	return 0;

}