#include <bits/stdc++.h>
using namespace std;
const int N = 105;
int a[N * 2];
int main() {
  int i, n, tot;
  scanf("%d", &n);
  tot = 0;
  for (i = 1; i <= 2 * n - 1; ++i) {
    scanf("%d", &a[i]);
    if (a[i] < 0) {
      a[i] = -a[i];
      tot++;
    }
  }
  sort(&a[1], &a[2 * n - 1]);
  int ans = 0;
  if (n % 2 == 1) {
    for (i = 1; i <= 2 * n - 1; ++i) ans += a[i];
  } else {
    for (i = 2 * n - 1; i >= 1; --i) ans += a[i];
    if (tot % 2 == 1) ans -= 2 * a[1];
  }
  printf("%d\n", ans);
  return 0;
}
