#include<bits/stdc++.h>
using namespace std;
using ll = long long;
#define all(a) begin(a), end(a)
#define rep(i,a,b) for(ll i = a; i < (b); i++)
#define per(i,a,b) for(ll i = (b)-1; i >= (a); i--)

int main(){
    int n;
    cin >> n;
    vector<ll> a(n);
    vector<ll> b(n-1);
    rep(i,0,n) cin >> a[i];
    rep(i,0,n-1) cin >> b[i];
    sort(all(a));
    sort(all(b));

    vector<ll> l(n,0);
    vector<ll> r(n,0);
    rep(i,0,n-1){
        l[i+1] = l[i] + abs(a[i] - b[i]);
    }
    per(i,1,n){
        r[i-1] = r[i] + abs(a[i] - b[i-1]);
    }
    ll ans = 1e18;
    set<ll> st;
    rep(i,0,n){
        if(ans > l[i] + r[i]){
            ans = l[i] + r[i];
            st.clear();
        }
        if(ans == l[i] + r[i]) st.insert(a[i]);
    }
    vector<ll>res(all(st));
    sort(all(res));
    cout << res.size() << endl;
    rep(i,0,res.size()){
        cout << res[i] << " \n"[i==res.size()-1];
    }
}