#include <bits/stdc++.h>
using namespace std;
int i, n, sum, ans;
int a[300];
int main() {
  scanf("%d", &n);
  for (i = 0; i < 2 * n - 1; i++) scanf("%d", &a[i]);
  if (n % 2) {
    sum = 0;
    for (i = 0; i < 2 * n - 1; i++) sum += abs(a[i]);
    printf("%d\n", sum);
    return 0;
  }
  sort(a, a + 2 * n - 1);
  sum = 0;
  for (i = 0; i < 2 * n - 1; i++) sum += a[i];
  ans = sum;
  for (i = 0; i < 2 * n - 2; i += 2) {
    sum -= 2 * (a[i] + a[i + 1]);
    ans = max(ans, sum);
  }
  printf("%d\n", ans);
  return 0;
}
