//両方から累積のあれ
#include <bits/stdc++.h>
using namespace std;
#define int long long

int N;

signed main(){
  cin>>N;
  vector<int> A(N);
  vector<int> B(N-1);
  for(int i = 0; i < N; i++) cin>>A[i];
  for(int i = 0; i < N-1; i++) cin>>B[i];
  sort(A.begin(),A.end());
  sort(B.begin(),B.end());
  vector<int> l(N);
  vector<int> r(N);
  for(int i = 1; i < N; i++) l[i] += l[i-1] + abs(A[i-1]-B[i-1]);
  for(int i = N-2; i >= 0; i--) r[i] += r[i+1] + abs(A[i+1]-B[i]);
  set<int> ans;
  int mini = 1e18;
  for(int i = 0; i < N; i++) mini = min(mini,l[i]+r[i]);
  for(int i = 0; i < N; i++) if(l[i] + r[i] == mini) ans.insert(A[i]);
  cout << ans.size() << endl;
  for(auto it = ans.begin(); it != ans.end(); ++it){
    cout << *it;
    it == prev(ans.end()) ? cout << endl : cout << " ";
  }
}