#include <bits/stdc++.h>
using namespace std;
#define forn(i,n) for(int i=0;i<int(n);i++)
#define forsn(i,s,n) for(int i=int(s);i<int(n);i++)
#define dforn(i,n) for(int i=int(n)-1;i>=0;i--)
#define dforsn(i,s,n) for(int i=int(n)-1;i>=int(s);i--)
#define fst first
#define snd second
#define pb push_back
#define eb emplace_back
#define sz(x) (int)x.size()
#define all(x) x.begin(), x.end()
typedef long long ll;
typedef vector<ll> vll;
typedef vector<int> vi;
typedef pair<int,int> ii;
int main(){
ios::sync_with_stdio(0);
cin.tie(0);
int n;
cin>>n;
vector<vi> cnt(n,vi(2));
ll ret=0;
forn(i,2*n){
int x,y;
cin>>x>>y;
--x,--y;
int nearX=min(max(x,0),n-1);
int nearY=min(max(y,0),1);
ll dist=abs(nearX-x)+abs(nearY-y);
cnt[nearX][nearY]++,ret+=dist;
}
int delta[2]={0,0};
forn(i,n){
forn(j,2) delta[j]+=cnt[i][j]-1;
forn(j,2) while(delta[j]<0&&delta[1-j]>0){
delta[j]++,delta[1-j]--,ret++;
}
ret+=abs(delta[0]+delta[1]);
}
cout<<ret<<'\n';
return 0;
}
