#include <bits/stdc++.h>
using namespace std;
void getre() {
  int x = 0;
  printf("%d\n", 1 / x);
}
void gettle() {
  int res = 1;
  while (1) res <<= 1;
  printf("%d\n", res);
}
template <typename T, typename S>
inline bool upmin(T &a, const S &b) {
  return a > b ? a = b, 1 : 0;
}
template <typename T, typename S>
inline bool upmax(T &a, const S &b) {
  return a < b ? a = b, 1 : 0;
}
template <typename N, typename PN>
inline N flo(N a, PN b) {
  return a >= 0 ? a / b : -((-a - 1) / b) - 1;
}
template <typename N, typename PN>
inline N cei(N a, PN b) {
  return a > 0 ? (a - 1) / b + 1 : -(-a / b);
}
template <typename N>
N gcd(N a, N b) {
  return b ? gcd(b, a % b) : a;
}
template <typename N>
inline int sgn(N a) {
  return a > 0 ? 1 : (a < 0 ? -1 : 0);
}
inline void gn(long long &x) {
  int sg = 1;
  char c;
  while (((c = getchar()) < '0' || c > '9') && c != '-')
    ;
  c == '-' ? (sg = -1, x = 0) : (x = c - '0');
  while ((c = getchar()) >= '0' && c <= '9') x = x * 10 + c - '0';
  x *= sg;
}
inline void gn(int &x) {
  long long t;
  gn(t);
  x = t;
}
inline void gn(unsigned long long &x) {
  long long t;
  gn(t);
  x = t;
}
inline void gn(double &x) {
  double t;
  scanf("%lf", &t);
  x = t;
}
inline void gn(long double &x) {
  double t;
  scanf("%lf", &t);
  x = t;
}
inline void gs(char *s) { scanf("%s", s); }
inline void gc(char &c) {
  while ((c = getchar()) > 126 || c < 33)
    ;
}
inline void pc(char c) { putchar(c); }
inline long long sqr(long long a) { return a * a; }
inline double sqrf(double a) { return a * a; }
const int inf = 0x3f3f3f3f;
const double pi = 3.14159265358979323846264338327950288L;
const double eps = 1e-6;
int n;
vector<int> s;
vector<int> gao(vector<int> &s) {
  sort((s).begin(), (s).end());
  s.resize(unique((s).begin(), (s).end()) - s.begin());
  if (((int)(s).size()) == 1) {
    return vector<int>();
  }
  if (((int)(s).size()) == 2) {
    if (abs(s[0]) == 1 || abs(s[1] == 1)) {
      vector<int> t;
      assert(!t.size());
      for (auto x : s) {
        if (x) t.push_back(x);
      }
      return t;
    }
  }
  int has1 = 0;
  for (auto x : s) {
    if (x & 1) {
      has1 = 1;
      break;
    }
  }
  if (!has1) {
    vector<int> ne;
    assert(!ne.size());
    for (auto x : s) {
      ne.push_back(x / 2);
    }
    vector<int> x = gao(ne);
    for (int i = (0), _ed = (((int)(x).size())); i < _ed; i++) {
      x[i] *= 2;
    }
    return x;
  } else {
    vector<int> ne = s;
    for (int i = (0), _ed = (((int)(ne).size())); i < _ed; i++) {
      if (ne[i] & 1) {
        ne[i]--;
      }
      ne[i] /= 2;
    }
    vector<int> x = gao(ne);
    for (int i = (0), _ed = (((int)(x).size())); i < _ed; i++) {
      x[i] *= 2;
    }
    x.push_back(1);
    ne = s;
    for (int i = (0), _ed = (((int)(ne).size())); i < _ed; i++) {
      if (ne[i] & 1) {
        ne[i]++;
      }
      ne[i] /= 2;
    }
    vector<int> y = gao(ne);
    for (int i = (0), _ed = (((int)(y).size())); i < _ed; i++) {
      y[i] *= 2;
    }
    y.push_back(-1);
    if (((int)(y).size()) < ((int)(x).size())) x = y;
    return x;
  }
}
int main() {
  int n;
  gn(n);
  while (n--) {
    int x;
    gn(x);
    s.push_back(x);
  }
  s.push_back(0);
  vector<int> t = gao(s);
  printf("%d\n", ((int)(t).size()));
  for (auto x : t) printf("%d ", x);
  return 0;
}
