#include <bits/stdc++.h>
using namespace std;
int main() {
  ios_base::sync_with_stdio(0);
  cin.tie(0);
  int n;
  cin >> n;
  int sum = 0, neg = 0;
  vector<int> arr(2 * n - 1);
  for (int i = 0; i < 2 * n - 1; i++) {
    cin >> arr[i];
    if (arr[i] < 0) {
      neg++;
      sum -= arr[i];
      arr[i] = -arr[i];
    } else
      sum += arr[i];
  }
  int t;
  if (neg % 2 == 1 && n % 2 == 0)
    t = 1;
  else
    t = 0;
  t = min(t, n - t);
  sort(arr.begin(), arr.end());
  for (int i = 0; i < t; i++) sum -= arr[i] * 2;
  cout << sum << endl;
}
