#include <bits/stdc++.h>
using namespace std;
template <class T>
void _R(T &x) {
  cin >> x;
}
void _R(int &x) { scanf("%d", &x); }
void _R(int64_t &x) { scanf("%lld", &x); }
void _R(double &x) { scanf("%lf", &x); }
void _R(char &x) { scanf(" %c", &x); }
void _R(char *x) { scanf("%s", x); }
void R() {}
template <class T, class... U>
void R(T &head, U &...tail) {
  _R(head);
  R(tail...);
}
template <class T>
void _W(const T &x) {
  cout << x;
}
void _W(const int &x) { printf("%d", x); }
void _W(const int64_t &x) { printf("%lld", x); }
void _W(const double &x) { printf("%.16f", x); }
void _W(const char &x) { putchar(x); }
void _W(const char *x) { printf("%s", x); }
template <class T, class U>
void _W(const pair<T, U> &x) {
  _W(x.first);
  putchar(' ');
  _W(x.second);
}
template <class T>
void _W(const vector<T> &x) {
  for (auto i = x.begin(); i != x.end(); _W(*i++))
    if (i != x.cbegin()) putchar(' ');
}
void W() {}
template <class T, class... U>
void W(const T &head, const U &...tail) {
  _W(head);
  putchar(sizeof...(tail) ? ' ' : '\n');
  W(tail...);
}
template <class T, class... U>
void DEBUG(const T &head, const U &...tail) {}
int MOD = 1e9 + 7;
void ADD(long long &x, long long v) {
  x = (x + v) % MOD;
  if (x < 0) x += MOD;
}
const int SIZE = 1e5 + 10;
int d[20][SIZE], a[SIZE], mi = 18;
int ans[20];
int tmp[20];
void dfs(int lv, int dn, int num) {
  if (num >= mi) return;
  if (!dn) {
    for (int i = 0; i < (num); ++i) ans[i] = tmp[i];
    mi = num;
    return;
  }
  if (lv > 18) return;
  int odd = 0;
  for (int i = 0; i < (dn); ++i) {
    if (d[lv][i] % 2) {
      odd = 1;
      break;
    }
  }
  if (!odd) {
    for (int i = 0; i < (dn); ++i) d[lv + 1][i] = d[lv][i] / 2;
    dfs(lv + 1, dn, num);
  } else {
    vector<int> dif{-1, 1};
    if (rand() & 1) swap(dif[0], dif[1]);
    for (int dd : dif) {
      int it = 0;
      for (int i = 0; i < (dn); ++i) {
        int nxt_v = 0;
        if (d[lv][i] % 2) {
          nxt_v = (d[lv][i] - dd) / 2;
        } else
          nxt_v = d[lv][i] / 2;
        if (!nxt_v) continue;
        if (it == 0 || d[lv + 1][it - 1] != nxt_v) {
          d[lv + 1][it++] = nxt_v;
        }
      }
      tmp[num] = dd * (1 << lv);
      dfs(lv + 1, it, num + 1);
    }
  }
}
int main() {
  int n;
  R(n);
  for (int i = 0; i < (n); ++i) {
    R(a[i]);
  }
  sort(a, a + n);
  n = unique(a, a + n) - a;
  int dn = 0;
  for (int i = 0; i < (n); ++i) {
    if (a[i]) d[0][dn++] = a[i];
  }
  dfs(0, dn, 0);
  W(mi);
  vector<int> res;
  if (mi == 18) {
    for (int i = 0; i < (mi - 1); ++i) res.push_back(1 << i);
    res.push_back(-(1 << 17));
  } else
    res = vector<int>(ans, ans + mi);
  W(res);
  return 0;
}
