#include <bits/stdc++.h>
using namespace std;
// * No One Dies a Virgin, Life Fucks Us All
typedef long long ll;
#define nl '\n'
#define ff first
#define ss second
#define pb push_back
#define sik(x) {cout << x << nl; return;}
constexpr ll maxn = 2e5+10, mod = 1e9 + 7, inf = 1e17, SQ = 450, LG = 20;
typedef pair<int, int> pii;
int n, x[maxn], y[maxn], cnt[maxn][3];
int32_t main() {
cin.tie(0)->sync_with_stdio(0);
cin >> n;
ll ans = 0;
for (int i = 1 ; i <= 2 * n ; i ++) {
cin >> x[i] >> y[i];
int nx = x[i], ny = y[i];
if (nx < 1) nx = 1;
if (nx > n) nx = n;
if (ny < 1) ny = 1;
if (ny > 2) ny = 2;
++ cnt[nx][ny];
ans += abs(x[i] - nx) + abs(y[i] - ny);
}
for (int i = 1 ; i <= n ; i ++) -- cnt[i][1], -- cnt[i][2];
for (int i = 1 ; i <= n ; i ++) {
cnt[i][1] += cnt[i - 1][1];
cnt[i][2] += cnt[i - 1][2];
if(cnt[i][1]>0 && cnt[i][2]<0){
int t = min(cnt[i][1], -cnt[i][2]);
cnt[i][1] -= t;
cnt[i][2] += t;
ans += t;
} else if (cnt[i][1] < 0 && cnt[i][2] > 0) {
int t = min(-cnt[i][1], cnt[i][2]);
cnt[i][1] += t;
cnt[i][2] -= t;
ans += t;
}
ans += abs(cnt[i][1]) + abs(cnt[i][2]);
}
cout << ans << nl;
}
