#include <bits/stdc++.h>
using namespace std;
const int N = 100100;
int n;
long long a[N];
int main() {
  cin >> n;
  for (int i = 0; i < n; i++) cin >> a[i];
  sort(a, a + n);
  reverse(a, a + n);
  long long A = 0LL, B = 0LL;
  for (int i = 0; i < n; i++)
    if (A < B)
      A += a[i];
    else
      B += a[i];
  cout << max(A, B) - min(A, B) + 1 << endl;
  return 0;
}
