#include <bits/stdc++.h>
using namespace std;
const int MOD = 998244353;
const int FFTMOD = 119 << 23 | 1;
const int INF = (int)1e9 + 23111992;
const long long LINF = (long long)1e18 + 23111992;
const long double PI = acos((long double)-1);
const long double EPS = 1e-9;
inline long long gcd(long long a, long long b) {
  long long r;
  while (b) {
    r = a % b;
    a = b;
    b = r;
  }
  return a;
}
inline long long lcm(long long a, long long b) { return a / gcd(a, b) * b; }
inline long long fpow(long long n, long long k, int p = MOD) {
  long long r = 1;
  for (; k; k >>= 1) {
    if (k & 1) r = r * n % p;
    n = n * n % p;
  }
  return r;
}
template <class T>
inline int chkmin(T& a, const T& val) {
  return val < a ? a = val, 1 : 0;
}
template <class T>
inline int chkmax(T& a, const T& val) {
  return a < val ? a = val, 1 : 0;
}
inline unsigned long long isqrt(unsigned long long k) {
  unsigned long long r = sqrt(k) + 1;
  while (r * r > k) r--;
  return r;
}
inline long long icbrt(long long k) {
  long long r = cbrt(k) + 1;
  while (r * r * r > k) r--;
  return r;
}
inline void addmod(int& a, int val, int p = MOD) {
  if ((a = (a + val)) >= p) a -= p;
}
inline void submod(int& a, int val, int p = MOD) {
  if ((a = (a - val)) < 0) a += p;
}
inline int mult(int a, int b, int p = MOD) { return (long long)a * b % p; }
inline int inv(int a, int p = MOD) { return fpow(a, p - 2, p); }
inline int sign(long double x) { return x < -EPS ? -1 : x > +EPS; }
inline int sign(long double x, long double y) { return sign(x - y); }
mt19937 mt(chrono::high_resolution_clock::now().time_since_epoch().count());
inline int myrand() { return abs((int)mt()); }
const int maxn = 5e5 + 5;
int n;
vector<int> a;
long long fen[2][maxn];
void upd(long long fen[], int p, int val) {
  p++;
  for (; p < maxn; p += p & -p) {
    fen[p] += val;
  }
}
long long query(long long fen[], int p) {
  p++;
  long long res = 0;
  for (; p > 0; p -= p & -p) {
    res += fen[p];
  }
  return res;
}
int checkup(int mi) {
  memset(fen, 0, sizeof(fen));
  vector<int> b = a;
  int ix = -1;
  for (int i = (n)-1; i >= (0); --i)
    if (b[i] > mi) {
      b.insert(b.begin() + i + 1, mi);
      ix = i + 1;
      break;
    }
  if (int((b).size()) == n) {
    ix = 0;
    b.insert(b.begin(), mi);
  }
  long long tot = accumulate((b).begin(), (b).end(), 0LL);
  for (int i = (n + 1) - 1; i >= (0); --i) {
    if (i >= ix) {
      int k = i + 1;
      long long x = (n - i) - query(fen[0], k);
      long long y = query(fen[1], k);
      long long sum = (long long)k * (k - 1) + x * k + y;
      if (tot > sum) {
        return 0;
      }
    }
    upd(fen[0], b[i], 1);
    upd(fen[1], b[i], b[i]);
    tot -= b[i];
  }
  return 1;
}
int findup() {
  int lo = -1, hi = n;
  while (lo < hi) {
    int mi = lo + hi + 1 >> 1;
    if (checkup(mi)) {
      lo = mi;
    } else {
      hi = mi - 1;
    }
  }
  return lo + hi >> 1;
}
int checkdn(int mi) {
  memset(fen, 0, sizeof(fen));
  vector<int> b = a;
  int ix = -1;
  for (int i = (n)-1; i >= (0); --i)
    if (b[i] > mi) {
      b.insert(b.begin() + i + 1, mi);
      ix = i + 1;
      break;
    }
  if (int((b).size()) == n) {
    ix = 0;
    b.insert(b.begin(), mi);
  }
  long long tot = accumulate((b).begin(), (b).end(), 0LL);
  for (int i = (n + 1) - 1; i >= (0); --i) {
    if (i < ix) {
      int k = i + 1;
      long long x = (n - i) - query(fen[0], k);
      long long y = query(fen[1], k);
      long long sum = (long long)k * (k - 1) + x * k + y;
      if (tot > sum) {
        return 0;
      }
    }
    upd(fen[0], b[i], 1);
    upd(fen[1], b[i], b[i]);
    tot -= b[i];
  }
  return 1;
}
int finddn() {
  int lo = 0, hi = n + 1;
  while (lo < hi) {
    int mi = lo + hi >> 1;
    if (!checkdn(mi)) {
      lo = mi + 1;
    } else {
      hi = mi;
    }
  }
  return lo + hi >> 1;
}
void chemthan() {
  cin >> n;
  a.resize(n);
  for (int& x : a) cin >> x;
  sort((a).begin(), (a).end()), reverse((a).begin(), (a).end());
  int x = finddn(), y = findup();
  long long k = accumulate((a).begin(), (a).end(), 0LL);
  vector<int> res;
  for (int i = (x); i < (y + 1); ++i) {
    if ((i & 1) == (k & 1)) {
      res.push_back(i);
    }
  }
  if (int((res).size()) == 0) {
    cout << -1 << "\n";
  } else {
    for (int i = (0); i < (int((res).size())); ++i)
      cout << res[i] << " \n"[i == int((res).size()) - 1];
  }
}
int main(int argc, char* argv[]) {
  ios_base::sync_with_stdio(0), cin.tie(0);
  if (argc > 1) {
    assert(freopen(argv[1], "r", stdin));
  }
  if (argc > 2) {
    assert(freopen(argv[2], "wb", stdout));
  }
  chemthan();
  cerr << "\nTime elapsed: " << 1000 * clock() / CLOCKS_PER_SEC << "ms\n";
  return 0;
}
