import java.util.*;
public class joi2019_ho_t4 {
public static void main(String[] args) {
Scanner scanner = new Scanner(System.in);
int N = scanner.nextInt();
int[][] coins = new int[2 * N][2];
for (int i = 0; i < 2 * N; i++) {
coins[i][0] = scanner.nextInt();
coins[i][1] = scanner.nextInt();
}
List<int[]> targets = new ArrayList<>();
for (int x = 1; x <= N; x++) {
for (int y = 1; y <= 2; y++) {
targets.add(new int[]{x, y});
}
}
Arrays.sort(coins, Comparator.comparingInt(a -> a[0]));
Collections.sort(targets, Comparator.comparingInt(a -> a[0]));
int totalMoves = 0;
for (int i = 0; i < 2 * N; i++) {
totalMoves += Math.abs(coins[i][0] - targets.get(i)[0]) + Math.abs(coins[i][1] - targets.get(i)[1]);
}
System.out.println(totalMoves);
}
}
