#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef __int128 lll;
typedef long double ld;
typedef pair<ll, ll> pll;
typedef pair<ld, ld> pld;
#define MAX 9223372036854775807LL
#define MIN -9223372036854775807LL
#define INF 0x3f3f3f3f3f3f3f3f
#define fi first
#define se second
#define fastio ios_base::sync_with_stdio(false); cin.tie(NULL); cout.tie(NULL); cout << fixed; cout.precision(10);
#define sp << " "
#define en << "\n"
#define compress(v) sort(v.begin(), v.end()), v.erase(unique(v.begin(), v.end()), v.end())
ll n;
pll a[200010];
ll ans;
ll cou[200010][3];
ll sum[3];
ll dist(ll x1, ll y1, ll x2, ll y2)
{
return abs(x1 - x2) + abs(y1 - y2);
}
int main(void)
{
fastio
cin >> n;
for(ll i = 1 ; i <= n * 2 ; i++)
{
cin >> a[i].fi >> a[i].se;
if(a[i].fi < 1)
{
ans += 1 - a[i].fi;
a[i].fi = 1;
}
else if(a[i].fi > n)
{
ans += a[i].fi - n;
a[i].fi = n;
}
if(a[i].se < 1)
{
ans += 1 - a[i].se;
a[i].se = 1;
}
else if(a[i].se > 2)
{
ans += a[i].se - 2;
a[i].se = 2;
}
cou[a[i].fi][a[i].se]++;
}
for(ll i = 1 ; i <= n ; i++)
{
sum[1] += cou[i][1] - 1;
sum[2] += cou[i][2] - 1;
if(sum[1] > 0 && sum[2] < 0)
{
ll gap = min(sum[1], -sum[2]);
ans += gap;
sum[1] -= gap;
sum[2] += gap;
}
else if(sum[2] > 0 && sum[1] < 0)
{
ll gap = min(sum[2], -sum[1]);
ans += gap;
sum[2] -= gap;
sum[1] += gap;
}
ans += abs(sum[1]) + abs(sum[2]);
}
cout << ans;
return 0;
}
