//#pragma optimize("Ofast")
//#pragma optimize("unroll-loops")
//#pragma traget("avx,avx2")
#include <iostream>
#include <cmath>
#include <algorithm>
#include <stdio.h>
#include <cstdint>
#include <cstring>
#include <string>
#include <cstdlib>
#include <vector>
#include <bitset>
#include <map>
#include <queue>
#include <ctime>
#include <stack>
#include <set>
#include <list>
#include <random>
#include <deque>
#include <functional>
#include <iomanip>
#include <sstream>
#include <fstream>
#include <complex>
#include <numeric>
#include <cassert>
#include <array>
#include <tuple>
#include <unordered_map>
#include <unordered_set>
#include <thread>
typedef long long ll;
typedef unsigned long long ull;
typedef long double ld;
#define el '\n'
#define ff first
#define ss second
#define pb push_back
#define pf push_front
#define popb pop_back
#define popf pop_front
#define point pair <ll, ll>
#define all(x) x.begin(), x.end()
#define rall(x) x.rbegin(), x.rend()
using namespace std;
#include <random>
mt19937 rnd(time(0));
const ll INF = 1e18 + 10;
const ll inf = 1e9 + 10;
const ll N = 2e5 + 10;
const ll mod = 1e9 + 7;
const ll K = 200;
const ll LOG = 8;
ll cnt[N][3];
void solve() {
ll n;
cin >> n;
vector <ll> x(2 * n), y(2 * n);
ll ans = 0;
for (ll i = 0; i < 2 * n; i++) {
cin >> x[i] >> y[i];
if (x[i] > n) ans += x[i] - n, x[i] = n;
if (x[i] < 1) ans += 1 - x[i], x[i] = 1;
if (y[i] < 1) ans += 1 - y[i], y[i] = 1;
if (y[i] > 2) ans += y[i] - 2, y[i] = 2;
cnt[x[i]][y[i]]++;
}
ll cur[2] = {0, 0};
for (ll i = 1; i <= n; i++) {
cur[0] += cnt[i][1] - 1;
cur[1] += cnt[i][2] - 1;
if (cur[0] > 0 && cur[1] < 0) {
ll x = min(abs(cur[0]), abs(cur[1]));
cur[0] -= x;
cur[1] += x;
ans += x;
} else if (cur[0] < 0 && cur[1] > 0) {
ll x = min(abs(cur[0]), abs(cur[1]));
cur[0] += x;
cur[1] -= x;
ans += x;
}
ans += abs(cur[0]) + abs(cur[1]);
}
cout << ans << el;
return;
}
signed main() {
ios_base::sync_with_stdio(0);
cin.tie(0); cout.tie(0);
int tests = 1;
//cin >> tests;
while (tests--)
solve();
return 0;
}
/*
*/
