#include <bits/stdc++.h>
using namespace std;
int main() {
  int n, i;
  long long int a[100010], b[100010], diff, mdiff;
  scanf("%d", &n);
  for (i = 0; i < n; i++) {
    scanf("%I64d", &a[i]);
  }
  sort(a, a + n);
  for (i = 0; i < n; i++) {
    b[i] = a[i];
  }
  for (i = 1; i < n; i++) {
    a[i] = a[i] + a[i - 1];
    b[n - i - 1] = b[n - i - 1] + b[n - i];
  }
  mdiff = 10e17;
  for (i = n - 1; i > 0; i--) {
    diff = b[i] - a[i - 1];
    if (diff < 0) diff *= -1;
    mdiff = diff < mdiff ? diff : mdiff;
  }
  cout << mdiff + 1;
  return 0;
}
