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, (a, b) -> a[0] == b[0] ? Integer.compare(a[1], b[1]) : Integer.compare(a[0], b[0]));
targets.sort((a, b) -> a[0] == b[0] ? Integer.compare(a[1], b[1]) : Integer.compare(a[0], b[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);
}
}
