#include <bits/stdc++.h>
using namespace std;
int main() {
  int n, c = 0, se = 0, so = 0, soo = 0, see = 0;
  cin >> n;
  int a[n];
  for (int i = 0; i < n; i++) {
    cin >> a[i];
    if (i % 2 == 0)
      so += a[i];
    else
      se += a[i];
  }
  for (int i = 0; i < n; i++) {
    if (i % 2 == 0)
      soo += a[i];
    else
      see += a[i];
    int t = se - see;
    int t1 = so - soo;
    if ((i + 1) % 2 == 0)
      see -= a[i];
    else
      soo -= a[i];
    if (see + t1 == soo + t) c++;
    if ((i + 1) % 2 == 0)
      see += a[i];
    else
      soo += a[i];
  }
  cout << c << endl;
  ;
  return 0;
}
