#include <bits/stdc++.h>
using namespace std;
#define int long long
#define pll pair<int, int>
#define mp make_pair
#define pb push_back
#define f first
#define s second
#define endl '\n'
#define ld long double
#define sz(x) static_cast<int>((x).size())
#define i5 tuple<int,int,int,int,int>
#define all(x) x.begin(), x.end()
#define iii tuple<int,int,int>
signed main(){
int n;cin>>n;
vector<pll> v(2*n);
for(int i=0;i<2*n;i++){
cin>>v[i].f>>v[i].s;
}
sort(all(v));
int ini=0;
vector<vector<int>> a(3, vector<int>(n+1, 0));
for(int i=0;i<2*n;i++){
int y=(v[i].s >= 2 ? 2 : 1), x=(v[i].f >= 1 and v[i].f <= n ? v[i].f : (v[i].f < 1 ? 1 : n));
ini += abs(v[i].s - y) + abs(v[i].f - x);
a[y][x]++;
}
vector<queue<int>> lol(3);
for(int i=2;i>=1;i--){
for(int j=1;j<=n;j++){
for(int k=0;k<a[i][j];k++){
lol[i].push(j);
}
//cout<<a[i][j]<<" ";
}
//cout<<endl;
}
int cont=0;
auto take1=[&](int x, int y){
cont += abs(y-1)+abs(x-lol[1].front());
lol[1].pop();
};
auto take2=[&](int x, int y){
cont += abs(y-2)+abs(x-lol[2].front());
lol[2].pop();
};
for(int x=1;x<=n;x++){
for(int y=2;y>=1;y--){
if(lol[1].empty() or lol[2].empty()){
if (lol[1].empty()) take2(x, y);
else take1(x, y);
}
else {
if(y==1){
if(lol[1].front() - 1 <= lol[2].front()) take1(x, y);
else take2(x, y);
}
if(y==2){
if(lol[2].front() - 1 <= lol[1].front()) take2(x, y);
else take1(x, y);
}
}
}
}
//printf("ini is %lld, cont is %lld\n", ini, cont);
cout<<ini+cont;
}
