#include <cstdio>
#include <stdio.h>
#include <stdbool.h>
#include <iostream>
#include <map>
#include <vector>
#include <climits>
#include <stack>
#include <string>
#include <queue>
#include <algorithm>
#include <set>
#include <unordered_set>
#include <unordered_map>
#include <cmath>
#include <cctype>
#include <bitset>
#include <iomanip>
#include <cstring>
#include <numeric>
#include <cassert>
using namespace std;
#define int long long
#define pii pair<int, int>
#define mp make_pair
#define pb push_back
#define fi first
#define se second
int32_t main(){
ios_base::sync_with_stdio(0);
cin.tie(0);
cout.tie(0);
int n, ans=0;
cin>>n;
vector<pii> vect(2*n);
for (int i=0; i<2*n; ++i)cin>>vect[i].fi>>vect[i].se;
sort(vect.begin(), vect.end());
multiset<pii> s;
for (int i=1, p=0; i<=n; ++i){
while (s.size()<2)s.insert(mp(vect[p].se, vect[p].fi)), ++p;
while (p<2*n&&vect[p].fi==vect[p-1].fi)s.insert(mp(vect[p].se, vect[p].fi)), ++p;
ans+=abs(s.begin()->fi-1)+abs(s.begin()->se-i);
ans+=abs((--s.end())->fi-2)+abs((--s.end())->se-i);
s.erase(s.begin());
s.erase((--s.end()));
}
cout<<ans;
}
