#include <bits/stdc++.h>
using namespace std;
using ld = long double;
using ll = long long;
const ll INF = 3e18, MOD = 1e9 + 7;
void solve();
signed main() {
#ifdef LOCAL
freopen("input.txt", "r", stdin);
freopen("output.txt", "w", stdout);
#endif
ios::sync_with_stdio(false);
cin.tie(0);
int q = 1;
while (q--) {
solve();
}
}
void solve() {
ll n; cin >> n;
vector<pair<ll, ll>> a(2 * n);
ll ans = 0;
for (int i = 0; i < 2 * n; i++) {
cin >> a[i].first >> a[i].second;
if (abs(1 - a[i].second) < abs(2 - a[i].second)) {
ans += abs(1 - a[i].second);
a[i].second = 1;
} else {
ans += abs(2 - a[i].second);
a[i].second = 2;
}
if (a[i].first < 1) {
ans += (1 - a[i].first);
a[i].first = 1;
}
if (a[i].first > n) {
ans += (a[i].first - n);
a[i].first = n;
}
}
vector<vector<ll>> cnt(n, vector<ll>(2));
for (int i = 0; i < 2 * n; i++) {
cnt[a[i].first - 1][a[i].second - 1]++;
}
ll f = 0;
ll c1 = 0, c2 = 0;
for (ll i = 0; i < n; i++) {
f += cnt[i][0] + cnt[i][1];
c1 += cnt[i][0], c2 += cnt[i][1];
ans += abs(f - (i + 1) * 2);
}
ans += (abs(n - c1) + abs(n - c2)) / 2;
cout << ans;
}
