#include <bits/stdc++.h>
using namespace std;
int num[100005];
int flag[100005] = {0};
int main() {
  int n;
  int nop = 0;
  scanf("%d", &n);
  for (int i = 1; i <= 2 * n - 1; i++) {
    scanf("%d", &num[i]);
    if (num[i] < 0) {
      nop++;
    }
  }
  int minp;
  if (nop % 2 == 0 && n % 2 == 0)
    minp = 0;
  else if (n % 2 == 1)
    minp = 0;
  else
    minp = 1;
  for (int i = 1; i <= 2 * n - 1; i++) {
    num[i] = abs(num[i]);
  }
  for (int i = 1; i <= minp; i++) {
    int mins = 1000000000;
    int wflag = 1;
    for (int j = 1; j <= 2 * n - 1; j++) {
      if (flag[j] == 0 && mins > num[j]) {
        mins = num[j];
        wflag = j;
      }
    }
    flag[wflag] = 1;
    num[wflag] = -num[wflag];
  }
  int sums = 0;
  for (int i = 1; i <= 2 * n - 1; i++) {
    sums += num[i];
  }
  printf("%d\n", sums);
}
