#include <bits/stdc++.h>
using namespace std;
int n, ans, a[20000];
int main() {
  cin >> n;
  for (int i = 1; i <= 2 * n - 1; i++) cin >> a[i];
  sort(a + 1, a + 2 * n - 1 + 1);
  int i, j;
  for (j = 2 * n - 1; j > 0 && a[j] >= 0; j--)
    ;
  if (j == n || (j % 2 == 0) || ((abs(j - n)) % 2 == 0)) {
    ans = 0;
    for (int i = 1; i <= 2 * n - 1; i++) ans += abs(a[i]);
    cout << ans;
    return 0;
  }
  ans = 0;
  for (i = 1; i <= 2 * n - 1; i++) ans += abs(a[i]);
  if (j == 2 * n - 1)
    ans += a[j] * 2;
  else if (a[j + 1] != 0)
    ans -= min(abs(a[j]), abs(a[j + 1])) * 2;
  cout << ans;
  return 0;
}
