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#include <iostream>
#include <vector>

using namespace std;

const int P = 1e9 + 7;

void brut3000(const vector<int>& nums, vector<int>& dp, int start, int end) {
    for(int i = start; i < end; ++i) {
        int sum = 0;
        for(int j = i; j >= 0; --j) {
            sum = (sum + nums[j]) % P;
            if(sum % 2 == 0) {
                dp[i] = (dp[i] + (j > 0 ? dp[j - 1] : 1)) % P; 
            }
        }
    }
}

void brut100(vector<int>& nums, vector<int>& dp, int end) {
    int lastOne = -1;
    dp[0] = 1 - (nums[0] % 2);
    if(dp[0] == 0) {
        lastOne = 0;
    }
    for(int i = 1; i < end; ++i) {
        if(nums[i] % 2 == 0) {
            dp[i] = (2 * dp[i - 1]) % P;
        } else {
            if(lastOne == 0) {
                dp[i] = 1;
            } else if(lastOne > 0) {
                dp[i] = (2 * dp[lastOne - 1]) % P;
            }
            lastOne = i;
        }
    }
}

pair<int, int> getLimit1(vector<int>& nums, int n) {
    pair<int, int> res(-1, 0);
    for(int i = 0; i < n; ++i) {
        res.second = (res.second + nums[i]) % P;
        if(res.second % 2 == 0) {
            res.first = i;
            break;
        }
    }

    return res;
}

pair<int, int> getLimit2(vector<int>& nums, int n) {
    pair<int, int> res(-1, 0);
    for(int i = n - 1; i >= 0; --i) {
        res.second = (res.second + nums[i]) % P;
        if(res.second % 2 == 0) {
            res.first = i;
            break;
        }
    }

    return res;
}

int getEnd(const vector<int>& nums, int n) {
    int sum = 0;
    for(int i = 0; i < n; ++i) {
        sum += nums[i];
        if(sum >= P) {
            return i;
        }
    }
    return n;
}

int allGood(vector<int>& nums, int n) {
    int sum = 0;
    for(int i = 0; i < n; ++i) {
        sum = (sum + nums[i]) % P;
    }
    if(sum % 2 == 0) {
        return 1;
    }
    return -1;
}


vector<int> compress(vector<int>& nums, int n, int & status) {
    vector<int> res;
    pair<int, int> limit1 = getLimit1(nums, n), limit2 = getLimit2(nums, n);
    if(limit1.first == -1 || limit2.first == -1) {
        status = -1;
        return res;
    }
    if(limit1.first >= limit2.first) {
        status = allGood(nums, n);
        return res;
    }
    nums[limit1.first] = limit1.second, nums[limit2.first] = limit2.second;
    for(int i = limit1.first; i <= limit2.first; ++i) {
        res.push_back(nums[i]);
    }
    status = 0;
    return res;
}

int main() {
    ios_base::sync_with_stdio(0);
    int n;
    cin >> n;
    vector<int> nums(n);

    for(int i = 0; i < n; ++i) {
        cin >> nums[i];
    }

    int status;
    vector<int> compressed = compress(nums, n, status);
    if(status == -1) {
        cout << "0\n";
        return 0;
    }
    if(status == 1) {
        cout << "1\n";
        return 0;
    }
    n = compressed.size();

    vector<int> dp(n), nums2(n);

    for(int i = 0; i < n; ++i) {
        nums2[i] = compressed[n - i - 1]; 
    }

    int end1 = getEnd(compressed, n), end2 = getEnd(nums2, n);

    if(end1 >= end2) {
        brut100(compressed, dp, end1);
        brut3000(compressed, dp, end1, n);
    } else {
        brut100(nums2, dp, end2);
        brut3000(nums2, dp, end2, n);
    }


    cout << dp[n - 1] << "\n";
}