#include <iostream>
#include <fstream>
#include <cassert>
#include <cmath>
#include <vector>
#include <algorithm>

using namespace std;

const int MAX_N = 10000;

typedef std::vector<int> V1D;
typedef std::vector<V1D> V2D;

vector<int> numbers;

void eraseRows(V2D & v, int row){
	//erase row
	v.erase(v.begin()+row);
}
void eraseColumns(V2D & v, int col){
	//erase column
	for(int i=0; i < (int)v.size(); ++i){
		v[i].erase(v[i].begin()+col);	
	}
}

void removeRC(V2D & v, int posI, int posJ){
	if(posI > posJ){
		eraseRows( v, posI ); eraseRows( v, posJ );
		eraseColumns( v, posI ); eraseColumns( v, posJ );
	}else{
		eraseRows( v, posJ ); eraseRows( v, posI );
		eraseColumns( v, posJ ); eraseColumns( v, posI );
	}
}

int main(){

	ifstream fin( "input.txt" ); assert( fin );

	int n, k;
	int posI = 0; int posJ = 0; int small = MAX_N; int costoTot = 0;

	fin >> n;
	int nTriplets = (n / 3);

	for( int i = 0; i < n; i++ ){
		fin >> k;
		numbers.insert( numbers.begin(),k );
	}

	fin.close();

	sort( numbers.begin(), numbers.end() );

	V2D diff( n, V1D(n) );

	for( int i = 0;i < n; i++){
		for( int j = 0; j < n; j++ ){
			diff[i][j] += abs( abs( (double)numbers[i] ) - abs( (double)numbers[j]) );
			if( diff[i][j] < small && j > i ){
					small = diff[i][j];
					posI = i;
					posJ = j;
			}
		}
	}
	
	costoTot += small; small = MAX_N;
 
	removeRC(diff, posI, posJ);

	n = n - 2; nTriplets--;


	while( nTriplets ){
		for(int i = 0; i < n; i++ ){
			for(int j = 0; j < n; j++ ){
				if( diff[i][j] < small && j > i ){
					small = diff[i][j];
					posI = i;
					posJ = j;
				}
			}
		}
		costoTot += small;
		small = MAX_N;
		
		removeRC(diff, posI, posJ);
		n = n - 2; nTriplets--;
		
	}

	ofstream fout("output.txt");
	fout << costoTot;
	fout.close();
	return 0;
}