#include<iostream>
using namespace std;
int gcd(int a, int b) {
  return b ? gcd(b, a%b) : a;
}
int main() {
  int N, A, ans;
  cin >> N >> ans;
  while(--N) {
    cin >> A;
    ans = gcd(ans, A);
  }
  cout << ans;
  return 0;
}