#include <bits/stdc++.h>
using namespace std;
const long long maxn = 2e5 + 12, mod = 1e9 + 7;
long long n, a[3][maxn], x[maxn], y[maxn];
set <int> Q[3];
int main(){
ios_base::sync_with_stdio(false), cin.tie(0);
cin >> n;
for(int i = 0; i < 2 * n; i++)
cin >> x[i] >> y[i];
long long d = 0;
for(int i = 0; i < 2 * n; i++){
if(y[i] < 1 || 2 < y[i]){
if(y[i] < 1){
d += 1 - y[i];
y[i] = 1;
}
else{
d += y[i] - 2;
y[i] = 2;
}
}
if(x[i] < 1 || n < x[i]){
if(x[i] < 1){
d += 1 - x[i];
x[i] = 1;
}
else{
d += x[i] - n;
x[i] = n;
}
}
a[y[i]][x[i]] += 1;
}
long long ans = 0;
/* cout << endl;
for(int i = 1; i <= n; i++)
cout << a[1][i] << ' ';
cout << endl;
for(int i = 1; i <= n; i++)
cout << a[2][i] << ' ';
cout << endl;*/
for(int i = 1; i <= n; i++){
if(a[1][i] == 0)
Q[1].insert(i);
if(a[2][i] == 0){
Q[2].insert(i);
}
while(a[1][i] > 1 && Q[1].size()){
ans += abs(*Q[1].begin() - i);
a[1][i] -= 1;
Q[1].erase(Q[1].begin());
}
while(a[2][i] > 1 && Q[2].size()){
ans += abs(*Q[2].begin() - i);
a[2][i] -= 1;
Q[2].erase(Q[2].begin());
}
while(a[1][i] > 1 && Q[2].size()){
ans += abs(*Q[2].begin() - i) + 1;
a[1][i] -= 1;
Q[2].erase(Q[2].begin());
}
while(a[2][i] > 1 && Q[1].size()){
ans += abs(*Q[1].begin() - i) + 1;
a[2][i] -= 1;
Q[1].erase(Q[1].begin());
}
while(a[1][i] > 1){
a[1][i + 1] += 1;
ans += 1;
a[1][i] -= 1;
// cout << i << endl;
}
while(a[2][i] > 1){
a[2][i + 1] += 1;
ans += 1;
a[2][i] -= 1;
}
}
cout << ans + d << endl;
}
