#include<bits/stdc++.h>
#define st first
#define nd second
#define mp make_pair
#define pb push_back
#ifndef LOCAL
#define cerr if(0)cerr
#endif
using namespace std;
using ll = long long;
using ld = long double;
using pii = pair<int, int>;
using vi = vector<int>;
int main() {
ios_base::sync_with_stdio(0);cin.tie(0);cout.tie(0);
int n; cin>>n;
vector<vector<int>> cnt(n+1, vector<int>(3));
ll ans = 0;
for(int i=0; i<2*n; ++i) {
ll x, y; cin>>x>>y;
ll nx = max(1LL, min((ll)n, x));
ll ny = max(1LL, min(2LL, y));
cnt[nx][ny]++;
ans += abs(x - nx) + abs(y - ny);
}
vector<int> filled(3);
for(int i=1; i<=n; ++i) {
for(int j=1; j<=2; ++j) {
int fill = min(i - filled[j], cnt[i][j]);
ans += (ll)(i-filled[j]-1) * fill - (ll)fill * (fill-1) / 2;
filled[j] += fill;
cnt[i][j] -= fill;
}
for(int j=1; j<=2; ++j) {
int fill = min(i - filled[j%2+1], cnt[i][j]);
ans += (ll)(i-filled[j%2+1]-1) * fill - (ll)fill * (fill-1) / 2 + (ll)fill;
filled[j%2+1] += fill;
cnt[i][j] -= fill;
}
if(i+1 <= n) {
for(int j=1; j<=2; ++j) {
ans += cnt[i][j];
cnt[i+1][j] += cnt[i][j];
}
}
}
cout<<ans;
}
