#include <bits/stdc++.h>
#include <atcoder/all>
using mint = atcoder::static_modint<998244353>;
// using mint = atcoder::static_modint<1000000007>;
using namespace std;
using namespace atcoder;
using ld = long double;
using ll = long long;
#define mp(a,b) make_pair(a,b)
#define rep(i,s,n) for(int i=s; i<n; i++)
const vector<int> dx{1,0,-1,0},dy{0,1,0,-1};

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(a.begin(),a.end());
    sort(b.begin(),b.end());
    vector<ll> left(n);
    rep(i,1,n)left[i]=left[i-1]+abs(a[i-1]-b[i-1]);
    vector<ll> right(n);
    for(int i=n-2; i>=0; i--)right[i]=right[i+1]+abs(a[i+1]-b[i]);
    ll ans=1e18;
    set<int> ids;
    rep(i,0,n){
        if(ans>left[i]+right[i]){
            ids.clear();
            ans=left[i]+right[i];
            ids.insert(a[i]);
        }
        else if(ans==left[i]+right[i])ids.insert(a[i]);
    }
    cout << ids.size() << "\n";
    for(auto x:ids)cout << x << " ";
}