#include <bits/stdc++.h>
#include <atcoder/all>
using namespace std;
using namespace atcoder;
#define all(x) (x).begin(), (x).end()
#define rep(i, n) for (int i = 0; i < (int)(n); i++)
#define rrep(i, n) for(int i = (int)(n - 1); i >= 0; i--)
template <typename T> bool chmax(T &a,const T &b){if(a<b){a=b;return true;}return false;}
template <typename T> bool chmin(T &a,const T &b){if(a>b){a=b;return true;}return false;}
using ll = long long;
#define int ll
using vi = vector<int>;
using vvi = vector<vector<int>>;
using vb = vector<bool>;
using vvb = vector<vector<bool>>;
using vs = vector<string>;
using pii = pair<int, int>;
/*
using mint = modint;
using vm = vector<mint>;
using vvm = vector<vector<mint>>;
*/

signed main(){
  int n; cin >> n;
  vi a(n), b(n - 1);
  rep(i, n) cin >> a.at(i);
  rep(i, n - 1) cin >> b.at(i);
  sort(all(a)); sort(all(b));
  segtree<int, [](int x, int y){return x + y;}, []{return 0ll;}> seg(n - 1);
  rep(i, n - 1) seg.set(i, abs(a.at(i) - b.at(i)));
  int min_score = seg.all_prod();
  set<int> ans = {a.at(n - 1)};
  for(int i = n - 2; i >= 0; i--){
  	seg.set(i, abs(a.at(i + 1) - b.at(i)));
  	if(seg.all_prod() < min_score){
  		min_score = seg.all_prod();
  		ans.clear();
  		ans.insert(a.at(i));
  	}
  	if(seg.all_prod() == min_score) ans.insert(a.at(i));
  }
  cout << ans.size() << endl;
  for(auto &w : ans) cout << w << ' ';
  cout << '\n';
}