#include <iostream>
#include <cstdint>
#include <vector>
#include <cmath>
#include <algorithm>

using namespace std;

int main()
{
	cin.tie(nullptr);
	ios::sync_with_stdio(false);

	int32_t N, i;
	cin >> N;
	vector<int32_t> A(N), B(N - 1);
	for (i = 0; i != N; ++i) cin >> A[i];
	for (i = 0; i != N - 1; ++i) cin >> B[i];

	vector<int64_t> l(N, 0), r(N, 0);
	sort(A.begin(), A.end()), sort(B.begin(), B.end());
	for (i = 1; i != N; ++i)
		l[i] = l[i - 1] + abs(A[i - 1] - B[i - 1]);
	for (i = N - 1; i != 0; --i)
		r[i - 1] = r[i] + abs(A[i] - B[i - 1]);

	vector<int32_t> L;
	int64_t min = INT64_MAX;
	for (i = 0; i != N; ++i)
	{
		if (min > l[i] + r[i])
			L.clear(), L.push_back(A[i]), min = l[i] + r[i];
		else if (min == l[i] + r[i] && A[i] != L.back())
			L.push_back(A[i]);
	}

	cout << L.size() << '\n' << L[0];
	for (i = 1; i != L.size(); ++i)
		cout << ' ' << L[i];
	cout << '\n';

	return 0;
}