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// Karol Kosinski 2021
#include <bits/stdc++.h>
// #define ENABLE_DEBUG
#define FOR(i,a,b) for(int i=(a),_b=(b);i<_b;++i)
#define FR_(i,a,b) for(int i=(a),_b=(b);i<=_b;++i)
#define FD_(i,b,a) for(int i=(b),_a=(a);i>=_a;--i)
#define ALL(c) (c).begin(),(c).end()
#define SIZE(c) int((c).size())
#define TIE(x...) int x;tie(x)
#define X first
#define Y second
#ifndef ENABLE_DEBUG
#define DEB(k,f,x...)
#else
#define DEB(k,f,x...) {if(k)printf("--------%4d : %s\n",__LINE__,__FUNCTION__);f(x);}
#endif
#define DEBL DEB(1,void,0)
#define DEBF(f,x...) DEB(1,f,x)
#define DEBUG(x...) DEB(0,printf,x)
using namespace std;
using LL = long long;
using ULL = unsigned long long;
using PII = pair<int, int>;
using TIII = tuple<int, int, int>;

constexpr int NX = 300'005;
constexpr int MOD = 1e9 + 7;

int A[NX], S[NX], P[NX];

int main()
{
    int n;
    scanf("%d", &n);
    FR_(i,1,n) scanf("%d", A + i);
    bool bigger = false;
    FR_(i,1,n)
    {
        S[i] = S[ i - 1 ] + A[i];
        if ( S[i] >= MOD ) bigger = true;
        if (bigger) S[i] %= MOD;
    }
    if (not bigger)
    {
        int k = 0, res = 1;
        FR_(i,1,n) if ( S[i] % 2 == 0 ) ++ k;
        FR_(i,2,k) res = ( res << 1 ) % MOD;
        if ( S[n] % 2 == 1 )
            printf("0\n");
        else
            printf("%d\n", res);
        return 0;
    }
    P[n] = ( A[n] % 2 == 0 );
    DEBUG("P[%2d] = %3d\n", n, P[n]);
    FD_(i,n-1,1)
    {
        int diff = ( S[n] + MOD - S[ i - 1 ] ) % MOD;
        P[i] = ( diff % 2 == 0 );
        FR_(j,i,n-1)
        {
            diff = ( S[j] + MOD - S[ i - 1 ] ) % MOD;
            if ( diff % 2 == 0 ) P[i] = ( P[i] + P[ j + 1 ] ) % MOD;
        }
        DEBUG("P[%2d] = %3d\n", i, P[i]);
    }
    printf("%d\n", P[1]);
    return 0;
}