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#include <bits/stdc++.h> 

using namespace std;

using ll = long long;

const ll MOD = 1e9+7;
const int MAX_N = 300007;

int n, curIter;
ll t[MAX_N];
ll pref[MAX_N], prefToSort[MAX_N];
unordered_map <ll, int> prefScale;

const int powlee = 1024 * 512 - 1;
ll evenTree[1024 * 1024 + 666];
ll oddTree[1024 * 1024 + 666];

void insertEvenTree(int x, ll val) {
  x += powlee;
  while (x >= 1) {
    evenTree[x] += val;
    evenTree[x] %= MOD;
    x /= 2;
  }
}

void insertOddTree(int x, ll val) {
  x += powlee;
  while (x >= 1) {
    oddTree[x] += val;
    oddTree[x] %= MOD;
    x /= 2;
  }
}

ll getEvenTree(int b, int e) {
  ll resVal = 0;
  b += powlee;
  b--;
  e += powlee;
  e++;
  while (b + 1 < e) {
    if(b % 2 == 0) {
      resVal += evenTree[b + 1];
    } 
    if(e % 2 == 1) {
      resVal += evenTree[e - 1];
    }
    resVal %= MOD;
    b /= 2;
    e /= 2;
  } 
  return resVal;
}

ll getOddTree(int b, int e) {
  ll resVal = 0;
  b += powlee;
  b--;
  e += powlee;
  e++;
  while (b + 1 < e) {
    if(b % 2 == 0) {
      resVal += oddTree[b + 1];
    } 
    if(e % 2 == 1) {
      resVal += oddTree[e - 1];
    }
    resVal %= MOD;
    b /= 2;
    e /= 2;
  } 
  return resVal;
}

int main() {
  ios_base::sync_with_stdio(0);
  cin.tie(0);
  cout.tie(0);
  cin >> n;
  t[0] = -1;
  for (int i = 1; i <= n; i++) {
    cin >> t[i];
    pref[i] = pref[i-1] + t[i];
    pref[i] %= MOD;
    prefToSort[i] = pref[i];
  }
  sort(prefToSort + 1, prefToSort + n + 1);
  prefScale[-1] = 0;
  curIter = 1;
  prefToSort[0] = -1; // guard
  for (int i = 1; i <= n; i++) {
    if (prefToSort[i] != prefToSort[i-1]) {
      prefScale[prefToSort[i]] = curIter;
      curIter++;
    }
  }
  prefScale[MOD] = curIter;
  insertEvenTree(0, 1);

  for (int i = 1; i < n; i++) {
    int scale = prefScale[pref[i]];
    ll resVal = 0;

    if (pref[i] % 2 == 0) {
      resVal += getEvenTree(0, scale); 
      resVal += getOddTree(scale, curIter);
      resVal %= MOD;
      //cout << pref[i] << " isEven: " << resVal << "\n";
      insertEvenTree(scale, resVal);
    }
    else {
      resVal += getOddTree(0, scale); 
      resVal += getEvenTree(scale, curIter);
      resVal %= MOD;
      //cout << pref[i] << " isOdd: " << resVal << "\n";
      insertOddTree(scale, resVal);
    }
  }
  int scale = prefScale[pref[n]];
  ll resVal = 0;
  if (pref[n] % 2 == 0) {
    resVal += getEvenTree(0, scale); 
    resVal += getOddTree(scale, curIter);
    resVal %= MOD;
    //cout << pref[n] << " isEven: " << resVal << "\n";
  }
  else {
    resVal += getOddTree(0, scale); 
    resVal += getEvenTree(scale, curIter);
    resVal %= MOD;
    //cout << pref[n] << " isOdd: " << resVal << "\n";
  }
  cout << resVal << "\n";
}