#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
using namespace __gnu_pbds;
#ifdef lisie_bimbi
#else
#define endl '\n'
#endif
typedef long long ll;
const int inf = 1000000000;
using namespace std;
#pragma GCC optimize("O3")
#pragma GCC target("avx,avx2,bmi2,fma,popcnt")
//#define int long long
int c[100000][2]{};
void solve(){
int n;
cin >> n;
ll ans = 0;
for(int i = 0; i < 2 * n; i++){
int x, y;
cin >> x >> y;
int x1 = x, y1 = y;
if(x <= 0){
x = 1;
}else if(x > n){
x = n;
}
if(y <= 0){
y = 1;
}else if(y > 2){
y = 2;
}
ans += abs(x1 - x) + abs(y1 - y);
c[x - 1][y - 1]++;
}
int now1 = 0, now2 = 0;
for(int i = 0; i < n; i++){
now1 += c[i][0] - 1;
now2 += c[i][1] - 1;
if((now1 > 0) && (now2 < 0)){
int k = min(now1, -now2);
now1 -= k;
now2 += k;
ans += k;
}else if((now1 < 0) && (now2 > 0)){
int k = min(-now1, now2);
now1 += k;
now2 -= k;
ans += k;
}
ans += abs(now1) + abs(now2);
}
cout << ans << endl;
}
signed main(){
#ifdef lisie_bimbi
freopen("input.txt", "r", stdin);
freopen("output.txt", "w", stdout);
#else
cin.tie(nullptr)->sync_with_stdio(false);
#endif
cout << setprecision(5) << fixed;
int _ = 1;
//cin >> t;
while(_--){
solve();
}
return 0;
}
