#include <bits/stdc++.h>
#include <atcoder/all>
using namespace std;
using namespace atcoder;
using ll = long long;
template<class T> inline bool chmax(T& a, T b) { if (a < b) { a = b; return true; } return false; }
template<class T> inline bool chmin(T& a, T b) { if (a > b) { a = b; return true; } return false; }
ll inf_ll = 9223372036854775807;
#define rep(i, n) for (ll i = 0; i < (ll)(n); i++)
using mint = atcoder::modint998244353;
using mint1 = atcoder::modint1000000007;
using Pa = std::pair<ll, ll>;

int Yes(bool x){
    if(x) cout << "Yes";
    else cout << "No";
    cout << endl;
    return 0;
}

int main(){
    ll N;
    cin >> N;
    vector<ll> A(N), B(N-1);
    rep(i, N){
        cin >> A[i];
    }
    rep(i, N-1){
        cin >> B[i];
    }
    sort(A.begin(), A.end());
    sort(B.begin(), B.end());
    vector<ll> C(N, 0), D(N, 0);
    rep(i, N-1){
        C[i+1] = C[i] + abs(A[i] - B[i]);
        D[i+1] = D[i] + abs(A[i+1] - B[i]);
    }
    vector<ll> ans(N);
    rep(i, N){
        ll y = 0;
        y += (C[i]-C[0]);
        y += (D[N-1]-D[i]);
        ans[i] = y;
    }
    ll x = ans[0];
    rep(i, N){
        chmin(x, ans[i]);
    }
    set<ll> S;
    rep(i, N){
        if(ans[i] == x){
            S.insert(A[i]);
        }
    }
    cout << S.size() << endl;
    for(auto i : S){
        cout << i << " ";
    }
}