#include <bits/stdc++.h>
using namespace std;
int main() {
cin.tie(0)->sync_with_stdio(0);
int n;
cin >> n;
vector<int> a(n);
for (auto& i : a) cin >> i;
auto mgcd = [](vector<int>& v) {
int ans = v[0];
for (auto i : v) ans = gcd(ans, i);
return ans;
};
if (n >= 8) {
cout << (mgcd(a) > 1) << endl;
return 0;
}
auto solve = [mgcd, n](auto self, vector<int> v, int us, int s) {
if (mgcd(v) == 1) return 1;
if (s == n) return 0;
for (int i = 0; i <= us; i++) {
v[s] += i;
if (self(self, v, us - i, s + 1)) return 1;
v[s] -= i;
}
return 0;
};
int ans = 0;
while (!solve(solve, a, ans, 0)) ans++;
cout << ans << endl;
}
