#include <bits/stdc++.h>
using namespace std;
using ll = long long;
const int sz = 1e4 + 10;
int ar[sz];
int main() {
  int n, m, sum, neg, chol;
  while (cin >> n) {
    m = n + n - 1;
    neg = 0;
    sum = 0;
    for (int i = 0; i < m; i++) {
      cin >> ar[i];
      if (ar[i] < 0) neg++;
      ar[i] = abs(ar[i]);
      sum += ar[i];
    }
    sort(ar, ar + m);
    if (neg % 2 && n % 2 == 0)
      chol = 1;
    else
      chol = 0;
    chol = min(chol, n - chol);
    for (int i = 0; i < chol; i++) sum -= ar[i] * 2;
    cout << sum << "\n";
  }
  return 0;
}
