#include <cstdio>
#include <iostream>
#include <string>
#include <sstream>
#include <stack>
#include <algorithm>
#include <cmath>
#include <queue>
#include <map>
#include <set>
#include <cstdlib>
#include <bitset>
#include <tuple>
#include <assert.h>
#include <deque>
#include <bitset>
#include <iomanip>
#include <limits>
#include <chrono>
#include <random>
#include <array>
#include <unordered_map>
#include <functional>
#include <complex>
#include <numeric>
template<class T> inline bool chmax(T& a, T b) { if (a < b) { a = b; return 1; } return 0; }
template<class T> inline bool chmin(T& a, T b) { if (a > b) { a = b; return 1; } return 0; }

const long long MAX = 5100000;
const long long INF = 1LL << 60;
const long long mod = 1000000007LL;
//const long long mod = 998244353LL;

using namespace std;
typedef unsigned long long ull;
typedef long long ll;

ll N;
ll a[200500];
ll sum[200500];
int main()
{
	/*
	cin.tie(nullptr);
	ios::sync_with_stdio(false);
	*/

	scanf("%lld", &N);
	for (ll i = 0; i < N; i++) scanf("%lld", &a[i]);
	sort(a, a + N);
	if (N == 2) {
		cout << a[1] - a[0] << endl;
		return 0;
	}

	ll dp[250000]; for (ll i = 0; i < 250000; i++) dp[i] = INF;
	dp[2] = a[1] - a[0];
	dp[3] = a[2] - a[0];
	for (ll i = 4; i <= N; i++) {
		ll id = i - 1;
		chmin(dp[i], dp[i - 2] + a[id] - a[id - 1]);
		chmin(dp[i], dp[i - 3] + a[id] - a[id - 2]);
	}
	cout << dp[N] << endl;
	return 0;
}