#include <iostream>
#include <vector>
#include <algorithm>
#include <math.h>
#define ll long long
using namespace std;
int main() {
ios_base::sync_with_stdio(0);
cin.tie(0);
int n;
cin >> n;
vector<int> a(n);
vector<int> b(n);
ll S = 0;
for (int i = 0; i < 2 * n; i++) {
ll x, y;
cin >> x >> y;
if (x <= 1) {
S += 1 - x;
x = 1;
}
if (x >= n) {
S += x - n;
x = n;
}
if (y >= 2) {
S += y - 2;
y = 2;
}
if (y <= 1) {
S += 1 - y;
y = 1;
}
if (y == 1) {
a[x - 1]++;
}
else
b[x - 1]++;
}
ll val = 0;
for (int i = 0; i < n; i++) {
val += a[i];
a[i] += b[i];
}
ll need = abs(val - n);
S += need;
ll now = 0;
for (int i = 0; i < n; i++) {
now += a[i];
need = abs(2 * (i + 1) - now);
S += need;
}
cout << S << endl;
}
