#include <cstdio>
#include <cstring>
#include <iostream>
#include <string>
#include <cmath>
#include <bitset>
#include <vector>
#include <map>
#include <set>
#include <queue>
#include <deque>
#include <algorithm>
#include <complex>
#include <unordered_map>
#include <unordered_set>
#include <random>
#include <cassert>
#include <fstream>
#define popcount __builtin_popcount
using namespace std;
typedef long long int ll;
typedef pair<int, int> P;
const ll MOD=1e9+7;
ll powmod(ll a, ll k){
    ll ap=a, ans=1;
    while(k){
        if(k&1){
            ans*=ap;
            ans%=MOD;
        }
        ap=ap*ap;
        ap%=MOD;
        k>>=1;
    }
    return ans;
}
ll inv(ll a){
	return powmod(a, MOD-2);
}
ll f[200001];
ll invf[200001];
ll calc(int x, int y){
	if(!(0<=y && y<=x)) return 0;
	return f[x+y]*invf[x]%MOD*invf[y]%MOD;
}
int main()
{
	int n; cin>>n;
	ll y[100010];
	for(int i=0; i<n; i++) cin>>y[i];
	sort(y, y+n);
	if(n==2){
		cout<<y[1]-y[0]<<endl; return 0;
	}
	ll dp[100010];
  dp[0]=1e18;
	dp[1]=y[1]-y[0];
	dp[2]=y[2]-y[0];
	for(int i=3; i<n; i++){
		dp[i]=min(dp[i-3]+y[i]-y[i-2], dp[i-2]+y[i]-y[i-1]);
	}
	cout<<dp[n-1]<<endl;
	return 0;
}