#include <bits/stdc++.h>
using namespace std;
int a[100005], b[100005];
bool cmp(int a, int b) { return a > b; }
int main() {
  int i, j, k, l;
  int t, m, n;
  while (cin >> n) {
    int la = 0, lb = 0;
    for (i = 1; i <= n + n - 1; i++) {
      cin >> j;
      if (j >= 0)
        a[++la] = j;
      else
        b[++lb] = j;
    }
    sort(b + 1, b + 1 + lb);
    sort(a + 1, a + 1 + la, cmp);
    for (i = 1; i <= lb; i++) {
      b[i] = -b[i];
    }
    if (lb % 2 == 1 && n % 2 == 0) {
      if (la != 0) {
        if (a[la] < b[lb])
          a[la] = -a[la];
        else
          b[lb] = -b[lb];
      } else {
        b[lb] = -b[lb];
      }
    }
    int ans = 0;
    for (i = 1; i <= la; i++) ans += a[i];
    for (i = 1; i <= lb; i++) ans += b[i];
    cout << ans << endl;
  }
  return 0;
}
