#include <bits/stdc++.h>
using namespace std;
long long pow(long long a, long long b, long long M) {
  long long t = 1;
  for (a %= M; b; b >>= 1) {
    if (b & 1) t = t * a % M;
    a = a * a % M;
  }
  return t;
}
inline int getc() {
  static const int N = 222;
  static char buf[N];
  static int n = 0, p = 0;
  if (p == n) p = 0, n = fread(buf, 1, N, stdin);
  if (p == n) exit(0);
  return buf[p++];
}
inline int R(int& first) {
  int f = 1, c = getc();
  first = 0;
  while (c <= 32) c = getc();
  if (c == '-') f = -1, c = getc();
  for (; '0' <= c && c <= '9'; c = getc()) first = first * 10 + c - '0';
  first *= f;
}
int a[55], n, ans;
int main() {
  cin >> n;
  n *= 2;
  ans = 1e9;
  for (int i = 1; i <= int(n); i++) cin >> a[i];
  sort(a + 1, a + n + 1);
  for (int i = 1; i <= int(n); i++)
    for (int j = i + 1; j <= int(n); j++) {
      int pre = 0, sum = 0;
      for (int k = 1; k <= int(n); k++)
        if (k != i && k != j) {
          if (pre == 0)
            pre = a[k];
          else
            sum += a[k] - pre, pre = 0;
        }
      ans = min(ans, sum);
    }
  cout << ans << endl;
}
