#include <bits/stdc++.h>
using namespace std;
const double eps = 1e-8;
int a[555];
int main() {
  int n, sum = 0;
  cin >> n;
  for (int i = 0; i < 2 * n - 1; i++) {
    cin >> a[i];
    sum += a[i];
  }
  sort(a, a + (2 * n - 1));
  int ans = sum;
  for (int i = 1; i <= 2 * n - 1; ++i) {
    if (i % 2 == 0) {
      int now = sum;
      for (int j = 0; j < i; ++j) {
        now -= 2 * a[j];
      }
      ans = max(ans, now);
    } else if (n % 2 == 1) {
      int now = sum;
      for (int j = 0; j < i; ++j) {
        now -= 2 * a[j];
      }
      ans = max(ans, now);
    }
  }
  cout << ans << endl;
  return 0;
}
