#include <bits/stdc++.h> using namespace std; using ll = long long; constexpr int nax = 1e5; int n, cnt[nax + 1][2], bil[2]; ll res; int main() { ios::sync_with_stdio(false); cin.tie(nullptr); cin >> n; for (int i = 1; i <= 2 * n; ++i) { int x, y; cin >> x >> y; res += max(0, x - n); res += max(0, 1 - x); res += max(0, y - 2); res += max(0, 1 - y); x = min(x, n); x = max(x, 1); y = min(y, 2); y = max(y, 1); ++cnt[x][y - 1]; } for (int i = 1; i <= n; ++i) { for (int j = 0; j < 2; ++j) bil[j] += cnt[i][j], --bil[j]; for (int j = 0; j < 2; ++j) if (bil[j] > 0 and bil[1 - j] < 0) { int q = min(-bil[1 - j], bil[j]); res += q; bil[j] -= q; bil[1 - j] += q; } for (int j = 0; j < 2; ++j) res += abs(bil[j]); } cout << res << '\n'; }