#include <bits/stdc++.h>
using namespace std;
#define rep(i, n) for(int i=0; i<n; i++)

#define chmin(x, y) x = min(x, y)
// #include <all.hpp>

#define int long long

signed main() {
  int n; cin >> n;
  vector<int> a(n);
  rep(i, n) cin >> a[i];
  vector<int> b(n-1);
  rep(i, n-1) cin >> b[i];
  sort(a.begin(), a.end());
  sort(b.begin(), b.end());
  int ans = 8'00000'00000LL;
  vector<int> l(n, 0), r(n, 0);
  rep(i,n){
    if(i==0)continue;
    l[i] = l[i-1] + abs(a[i-1] - b[i-1]);
    r[i] = r[i-1] + abs(a[i] - b[i-1]);
  }
  int tmp = r.back();
  // reverse(r.begin(), r.end());
  rep(i, n){
    r[i] = tmp - r[i];
  }
  rep(i, n){
    chmin(ans, l[i] + r[i]);
  }

  set<int> st;
  rep(i,n) {
    if(l[i] + r[i] == ans) {
      st.insert(a[i]);
    }
  }
  cout << st.size() << endl;
  for(auto x: st) cout << x << " ";
}