#include <bits/stdc++.h>
using namespace std;
using ll = long long;
ll INF = 1e18;
ll n;
vector<pair<ll, ll>> s;
vector<vector<ll>> pref;
ll an(ll x, ll y) {
ll ans = 0;
pref.assign(2, vector<ll>(n, 0));
for (ll i = 0; i < s.size(); i++) {
if (s[i].first < x) {
if (s[i].second <= y) {
ans += abs(x - s[i].first) + abs(y - s[i].second);
pref[1][0]++;
continue;
} else {
ans += abs(x - s[i].first) + abs((y + 1) - s[i].second);
pref[0][0]++;
continue;
}
}
if (s[i].first > x + n - 1) {
if (s[i].second <= y) {
ans += abs((x + n - 1) - s[i].first) + abs(y - s[i].second);
pref[1][n - 1]++;
continue;
} else {
ans += abs((x + n - 1) - s[i].first) + abs((y + 1) - s[i].second);
pref[0][n - 1]++;
continue;
}
}
if (y + 1 <= s[i].second) {
ans += abs((y + 1) - s[i].second);
pref[0][s[i].first - x]++;
} else {
ans += abs((y) - s[i].second);
pref[1][s[i].first - x]++;
}
}
deque<ll> d1, d2;
deque<ll> cool1, cool2;
for (ll j = 0; j < n; j++) {
if (pref[0][j] == 0) {
d1.push_back(j);
}
if (pref[1][j] == 0) {
d2.push_back(j);
}
if (!cool1.empty() && !d1.empty()) {
ans += abs(j - cool1.front());
cool1.pop_front();
d1.pop_front();
}
if (!cool2.empty() && !d2.empty()) {
ans += abs(j - cool2.front());
cool2.pop_front();
d2.pop_front();
}
if (!cool1.empty() && !d2.empty()) {
ans += abs(j - cool1.front()) + 1;
cool1.pop_front();
d2.pop_front();
}
if (!cool2.empty() && !d1.empty()) {
ans += abs(j - cool2.front()) + 1;
cool2.pop_front();
d1.pop_front();
}
while (!d1.empty() && pref[0][j] > 1) {
ans += j - d1.front();
d1.pop_front();
pref[0][j]--;
}
if (d1.empty() && pref[0][j] > 1) {
for (ll e = 1; e < pref[0][j]; e++) {
cool1.push_back(j);
}
}
while (!d2.empty() && pref[1][j] > 1) {
ans += j - d2.front();
d2.pop_front();
pref[1][j]--;
}
if (d2.empty() && pref[1][j] > 1) {
for (ll e = 1; e < pref[1][j]; e++) {
cool2.push_back(j);
}
}
while (!cool1.empty() && !d2.empty()) {
ans += abs(d2.front() - cool1.front()) + 1;
cool1.pop_front();
d2.pop_front();
}
while (!cool2.empty() && !d1.empty()) {
ans += abs(d1.front() - cool2.front()) + 1;
cool2.pop_front();
d1.pop_front();
}
}
return ans;
}
int main() {
ios::sync_with_stdio(false);
cin.tie(nullptr);
cout.tie(nullptr);
cin >> n;
s.assign(n * 2, {});
for (ll i = 0; i < n * 2; i++) {
cin >> s[i].first >> s[i].second;
}
cout << an(1, 1);
}
// 3
// 0 0
// 0 4
// 4 0
// 2 1
// 2 5
// -1 1
