#include <bits/stdc++.h>
using namespace std;
template <class T>
void rd(T &ret) {
  ret = 0;
  bool ok = 0, u = 0;
  for (;;) {
    int c = getchar();
    if (c >= '0' && c <= '9')
      ret = (ret << 3) + (ret << 1) + c - '0', ok = 1;
    else if (c == '-')
      u = 1;
    else if (ok) {
      if (u) ret *= -1;
      return;
    }
  }
}
long long pow_mod(long long p, long long n, long long mod) {
  long long ret = 1;
  for (; n; n >>= 1) {
    if (n & 1) ret = ret * p % mod;
    p = p * p % mod;
  }
  return ret;
}
template <class T>
bool chmin(T &a, const T &b) {
  return b < a ? a = b, 1 : 0;
}
template <class T>
bool chmax(T &a, const T &b) {
  return b > a ? a = b, 1 : 0;
}
int gcd(int a, int b) { return b ? gcd(b, a % b) : a; }
const int N = (int)1e5 + 9;
bool hasp[N], hasn[N];
long long ans, temp_ans;
void output_ans() {
  cout << __builtin_popcountll(ans) << endl;
  while (ans) {
    int t = __builtin_ctzll(ans);
    if (t < 21)
      printf("%d ", 1 << t);
    else
      printf("-%d ", 1 << (t - 21));
    ans ^= 1ll << t;
  }
}
void add(const int &t, vector<int> &tn, bool &odd) {
  if (!t) return;
  if (t & 1) odd = 1;
  if (tn.empty() || tn.back() < t) tn.push_back(t);
}
void dfs(int p, const vector<int> &pn, const vector<int> &nn, bool odd) {
  int mx = 0;
  if (((int)(pn).size())) chmax(mx, pn.back());
  if (((int)(nn).size())) chmax(mx, nn.back());
  if (mx == 1) {
    if (((int)(pn).size())) temp_ans |= (1ll << p);
    if (((int)(nn).size())) temp_ans |= (1ll << (p + 21));
    if (__builtin_popcountll(ans) > __builtin_popcountll(temp_ans))
      ans = temp_ans;
    if (((int)(pn).size())) temp_ans ^= (1ll << p);
    if (((int)(nn).size())) temp_ans ^= (1ll << (p + 21));
    return;
  }
  bool new_odd = 0;
  vector<int> npn, nnn;
  if (!odd) {
    int t;
    for (int i : pn) {
      t = i / 2;
      add(t, npn, new_odd);
    }
    for (int i : nn) {
      t = i / 2;
      add(t, nnn, new_odd);
    }
    dfs(p + 1, npn, nnn, new_odd);
  } else {
    int d = 1, t;
    for (int i : pn) {
      if (i & 1)
        t = (i - d) / 2;
      else
        t = i / 2;
      add(t, npn, new_odd);
    }
    for (int i : nn) {
      if (i & 1)
        t = (i + d) / 2;
      else
        t = i / 2;
      add(t, nnn, new_odd);
    }
    temp_ans |= (1ll << p);
    dfs(p + 1, npn, nnn, new_odd);
    temp_ans ^= (1ll << p);
    new_odd = 0;
    npn.clear();
    nnn.clear();
    d = -1;
    for (int i : pn) {
      if (i & 1)
        t = (i - d) / 2;
      else
        t = i / 2;
      add(t, npn, new_odd);
    }
    for (int i : nn) {
      if (i & 1)
        t = (i + d) / 2;
      else
        t = i / 2;
      add(t, nnn, new_odd);
    }
    temp_ans |= (1ll << (21 + p));
    dfs(p + 1, npn, nnn, new_odd);
    temp_ans ^= (1ll << (21 + p));
  }
}
int main() {
  int n;
  cin >> n;
  bool odd = 0;
  for (int i = (0); i < (n); i++) {
    int t;
    scanf("%d", &t);
    if (t > 0) {
      hasp[t] = 1;
      if (t & 1) odd = 1;
    } else if (t < 0) {
      hasn[-t] = 1;
      if ((-t) & 1) odd = 1;
    }
  }
  vector<int> pn, nn;
  for (int i = (1); i < (N - 1); i++) {
    if (hasp[i]) pn.push_back(i);
    if (hasn[i]) nn.push_back(i);
  }
  temp_ans = 0;
  ans = (1ll << 50) - 1;
  if (((int)(pn).size()) || ((int)(nn).size()))
    dfs(0, pn, nn, odd);
  else
    ans = 0;
  output_ans();
  return 0;
}
