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/* 2021
 * Maciej Szeptuch
 */
#include <cmath>
#include <cstdio>
#include <queue>

const int MOD = 1000000007;
int length;
int number[524288];
int result[524288];
int other[524288];
long long int sum;

int main(void)
{
    scanf("%d", &length);
    for(int n = 1; n <= length; ++n)
        scanf("%d", &number[n]);

    result[0] = 1;
    for(int n = 1; n <= length; ++n)
    {
        sum += number[n];
        if(sum < MOD)
        {
            if(number[n] % 2 == 1)
            {
                result[n] = other[n - 1];
                other[n] = (n > 1 ? 2 * result[n - 1] : 1) % MOD;
            }

            else
            {
                result[n] = (n > 1 ? 2 * result[n - 1] : 1) % MOD;
                other[n] = other[n - 1];
            }
        }

        else
        {
            result[n] = 0;
            int suffix = 0;
            for(int s = n; s > 0; --s)
            {
                suffix = (suffix + number[s]) % MOD;
                if(suffix % 2 == 0)
                    result[n] = (result[n] + result[s - 1]) % MOD;
            }
        }
    }

    printf("%d\n", result[length]);
    return 0;
}