#include <bits/stdc++.h>
using namespace std;
using ll = long long;
using ld = long double;
#define fi first
#define se second
#define vi vector<int>
#define vll vector<long long>
#define pii pair<int, int>
#define pll pair<long long, long long>
#define pb push_back
#define mp make_pair
#define eb emplace_back
#define all(x) (x).begin(), (x).end()
#define sz(x) (int)(x).size()
mt19937 rng(chrono::high_resolution_clock::now().time_since_epoch().count());
mt19937_64 rng64(chrono::high_resolution_clock::now().time_since_epoch().count());
inline int rand(int l,int r){return uniform_int_distribution<int>(l, r)(rng);}
inline ll rand(ll l,ll r){return uniform_int_distribution<ll>(l, r)(rng64);}
#ifdef DEBUG
auto&operator<<(auto&o,pair<auto,auto>p){return o<<"("<<p.first<<", "<<p.second<<")";}
auto operator<<(auto&o,auto x)->decltype(x.end(),o){o<<"{";int i=0;for(auto e:x)o<<","+!i++<<e;return o<<"}";}
#define debug(X...)cerr<<"["#X"]: ",[](auto...$){((cerr<<$<<"; "),...)<<endl;}(X)
#else
#define debug(...){}
#endif
struct custom_hash {
static uint64_t splitmix64(uint64_t x) {
x += 0x9e3779b97f4a7c15;
x = (x ^ (x >> 30)) * 0xbf58476d1ce4e5b9;
x = (x ^ (x >> 27)) * 0x94d049bb133111eb;
return x ^ (x >> 31);
}
size_t operator()(uint64_t x) const {
static const uint64_t FIXED_RANDOM = chrono::steady_clock::now().time_since_epoch().count();
return splitmix64(x + FIXED_RANDOM);
}
};
struct pair_hash{
size_t operator()(const pair<int,int>&x)const{
return hash<long long>()(((long long)x.first)^(((long long)x.second)<<32));
}
};
const int MAXN = 1e5 + 7;
ll cnt[3][MAXN];
ll n;
int main(){
ios_base::sync_with_stdio(0);
cin.tie(NULL);
cout.tie(NULL);
cin >> n;
ll ans = 0LL;
for(int i = 1; i <= 2 * n; i++){
ll x, y;
cin >> x >> y;
ll nx = min(max(x, 1LL), n);
ll ny = min(max(y, 1LL), 2LL);
ans = (ll)ans + abs(x - nx) + abs(y - ny);
cnt[ny][nx]++;
}
ll c[3] = {0LL, 0LL, 0LL};
for(int i = 1; i <= n; i++){
cnt[1][i]--;
cnt[2][i]--;
if(cnt[1][i] < 0LL && cnt[2][i] > 0LL){
c[0] = min(-cnt[1][i], cnt[2][i]);
ans += c[0];
cnt[2][i] -= c[0];
cnt[1][i] += c[0];
}else if(cnt[2][i] < 0LL && cnt[1][i] > 0LL){
c[0] = min(cnt[1][i], -cnt[2][i]);
ans += c[0];
cnt[2][i] += c[0];
cnt[1][i] -= c[0];
}
ans += (abs(cnt[1][i]) + abs(cnt[2][i]));
cnt[1][i + 1] += cnt[1][i];
cnt[2][i + 1] += cnt[2][i];
}
cout << ans << '\n';
return 0;
}
