#include <bits/stdc++.h>
using namespace std;
#define int long long
int n;
const int MXN = 100005;
int x[MXN * 2], y[MXN * 2];
int at[MXN][3];
int pf[MXN][3];
int ans;
signed main() {
cin >> n;
for (int i=0; i<2*n; i++) {
int x, y;
cin >> x >> y;
if (x < 1) {
ans += (1 - x);
x = 1;
}
if (x > n) {
ans += (x - n);
x = n;
}
if (y < 1) {
ans += (1 - y);
y = 1;
}
if (y > 2) {
ans += (y - 2);
y = 2;
}
at[x][y]++;
}
for (int i=1; i<=n; i++) {
for (int j=1; j<=2; j++) {
pf[i][j] = at[i][j] + pf[i-1][j] + pf[i][j-1] - pf[i-1][j-1];
}
}
ans += abs(pf[n][1] - n);
for (int i=1; i<=n; i++) {
int x = pf[i][2];
ans += abs(2 * i - x);
}
cout << ans << endl;
}
