#include <bits/stdc++.h>
using namespace std;
#define kath ash
int cnt[100005][5];
int main() {
int n;
cin >> n;
long long ans = 0;
for (int i = 0; i < 2 * n; ++i) {
int x, y;
cin >> x >> y;
int nx = max(1, min(n, x));
int ny = max(1, min(2, 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 += 1ll * (i - filled[j] - 1) * fill - 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 += 1ll * (i - filled[j % 2 + 1] - 1) * fill - fill * (fill - 1) / 2 + 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 << endl;
}
