#include <bits/stdc++.h> // #include <atcoder/all> using namespace std; // using namespace atcoder; #define rep(i, a, n) for(int i = a; i < n; i++) #define rrep(i, a, n) for(int i = a; i >= n; i--) #define inr(l, x, r) (l <= x && x < r) #define ll long long #define ld long double // using mint = modint1000000007; // using mint = modint998244353; constexpr int IINF = 1001001001; constexpr ll INF = 1e18; template<class t,class u> void chmax(t&a,u b){if(a<b)a=b;} template<class t,class u> void chmin(t&a,u b){if(b<a)a=b;} int main(){ int n; cin >> n; vector<ll> a(n), b(n-1); rep(i, 0, n) cin >> a[i]; rep(i, 0, n-1) cin >> b[i]; sort(a.begin(), a.end()); sort(b.begin(), b.end()); vector<ll> acc_l(n+1), acc_r(n+1); rep(i, 0, n-1){ acc_l[i+1] = acc_l[i]+abs(a[i]-b[i]); } rrep(i, n-1, 1){ acc_r[i] = acc_r[i+1]+abs(a[i]-b[i-1]); } ll mi = INF; rep(i, 0, n){ chmin(mi, acc_l[i]+acc_r[i+1]); } set<int> l; rep(i, 0, n){ if(acc_l[i]+acc_r[i+1] == mi){ l.insert(a[i]); } } cout << l.size() << endl; for(auto L: l){ cout << L << ' '; } cout << endl; return 0; }