#include <bits/stdc++.h>
#define FI first
#define SE second
#define PB push_back
#define ll long long
#define FOR(i,a,b) for(int i=a;i<b;++i)
#define ROF(i,a,b) for(int i=b-1;i>=a;--i)
#define YES(i) cout<<(i?"YES":"NO")<<endl
#define Yes(i) cout<<(i?"Yes":"No")<<endl
#define co(i) cout<<(i)<<endl
#define fcout cout<<fixed<<setprecision(10)
#define uni(i) i.erase(unique(i.begin(), i.end()), i.end());
#define all(i) i.begin(),i.end()
#define pint pair<int, int>
#define vint vector<int>
using namespace std;

const int INF=1e9+7;
const ll LINF=1e18;
const int MOD=1e9+7;
//const int MOD=998244353;

ll y[100000],dp[100000];

int main(){
	int n; cin>>n;
	assert(n>=2 && n<=100000);
	FOR(i,0,n){
		cin>>y[i];
		assert(-1e9<=y[i] && y[i]<=1e9);
	}
	sort(y,y+n);
	dp[0]=LINF;
	dp[1]=y[1]-y[0];
	dp[2]=y[2]-y[0];
	FOR(i,3,n){
		dp[i]=min(dp[i-3]+y[i]-y[i-2],dp[i-2]+y[i]-y[i-1]);
	}
	co(dp[n-1]);
}