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#include <algorithm>
#include <cstdio>

const int mod = 1000000007;
const int max_n = 400000;
int n;
int a[max_n];
int mmap[max_n];
int dp[max_n];
std::pair<int, int> b[max_n];

const int czapa = 524288;
int odd[2 * czapa + 1];
int even[2 * czapa + 1];

void add(int tree[], int index, int val) {
  index += czapa;
  tree[index] += val; if (tree[index] >= mod) tree[index] -= mod;
  while (index > 1) {
    index /= 2;
    tree[index] += val; if (tree[index] >= mod) tree[index] -= mod;
  }
}

int count_le(int tree[], int index) {
  ++index;
  index += czapa;
  int ret = 0;
  while (index > 1) {
    if (index % 2 == 1) {
      ret += tree[index - 1];
      if (ret >= mod) ret -= mod;
    }
    index /= 2;
  }
  return ret;
}

int count_a(int tree[], int index) {
  index += czapa;
  int ret = 0;
  while (index > 1) {
    if (index % 2 == 0) {
      ret += tree[index + 1];
      if (ret >= mod) ret -= mod;
    }
    index /= 2;
  }
  return ret;
}

int main() {
  for (int i = 0; i < 2 * czapa + 1; ++i) odd[i] = even[i] = 0;

  scanf("%d", &n);
  a[0] = 0;
  b[0].first = 0;
  b[0].second = 0;
  for (int i = 1; i <= n; ++i) {
    scanf("%d", a + i);
    a[i] = a[i] + a[i - 1];
    if (a[i] >= mod) a[i] -= mod;
    b[i].first = a[i];
    b[i].second = i;
  }
  std::sort(b, b + n + 1);
  int cnt = 0;
  for (int i = 0; i < n + 1; ++i) {
    if (i != 0 && b[i] != b[i - 1]) {
      ++cnt;
    }
    mmap[b[i].second] = cnt;
  }
  add(even, mmap[0], 1);
  dp[0] = 1;
  for (int i = 1; i <= n; ++i) {
    dp[i] = 0;
    if (a[i] % 2 == 0) {
      dp[i] = (count_le(even, mmap[i]) + count_a(odd, mmap[i])) % mod; 
      add(even, mmap[i], dp[i]);
    } else {
      dp[i] = (count_le(odd, mmap[i]) + count_a(even, mmap[i])) % mod; 
      add(odd, mmap[i], dp[i]);
    }
  }
  printf("%d\n", dp[n]);
  return 0;
}