#include<bits/stdc++.h> #include <ext/pb_ds/assoc_container.hpp> #include <ext/pb_ds/tree_policy.hpp> using namespace __gnu_pbds; using namespace std; template<class T> using ordered_set = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>; template<class T, class U> using ordered_map = tree<T, U, less<T>, rb_tree_tag, tree_order_statistics_node_update>; #define ll long long #define MOD 1000000007 #define MAXN 2e5 #define SIZE 314 #define pb push_back ll power(ll a, ll b){ if (b == 0) return 1; ll res = power(a, b / 2); if (b % 2 == 1) return res * res % MOD * a % MOD; return res * res % MOD; // if (b % 2 == 1) return res * res * a; // return res * res; } int main(){ // ios_base::sync_with_stdio(0); // cin.tie(0); // cout.tie(0); ll n; cin >> n; vector<pair<ll, ll>> nums(2 * n); for (int i = 0; i < 2 * n; i++){ ll x, y; cin >> x >> y; nums[i] = {x, y}; } vector<vector<ll>> cnt(n + 1, vector<ll>(3, 0)); ll ans = 0; for (int i = 0; i < 2 * n; i++){ auto [x, y] = nums[i]; if (x >= 1 && x <= n && y >= 1 && y <= 2){ cnt[x][y]++; continue; } if (x >= 1 && x <= n){ if (y > 2){ cnt[x][2]++; ans += y - 2; continue; } else{ cnt[x][1]++; ans += 1 - y; continue; } } else if (y >= 1 && y <= 2){ if (x < 1){ cnt[1][y]++; ans += 1 - x; } else{ cnt[n][y]++; ans += x - n; } continue; } else{ if (x < 1){ if (y < 1){ cnt[1][1]++; ans += (1 - x) + (1 - y); } else{ cnt[1][2]++; ans += (1 - x) + (y - 2); } } else{ if (y < 1){ cnt[n][1]++; ans += (x - n) + (1 - y); } else{ cnt[n][2]++; ans += (x - n) + (y - 2); } } } } // cout << ans << " GG\n"; // for (int j = 1; j <= 2; j++){ // for (int i = 1; i <= n; i++){ // cout << cnt[i][j] << " "; // } // cout << "\n"; // } // queue<tuple<int, int, int, int, int>> q; // for (int i = 1; i <= n; i++){ // for (int j = 1; j <= 2; j++){ // if (cnt[i][j] > 1){ // q.push({i, j, 0, i, j}); // } // } // } // int xDir[] = {0, 0, -1, 1}; // int yDir[] = {-1, 1, 0, 0}; // while(!q.empty()){ // auto [x, y, cost, oriX, oriY] = q.front(); // q.pop(); // if (cnt[oriX][oriY] <= 1){ // continue; // } // for (int i = 0; i < 4; i++){ // // } // } ll lastYes = n; for (int i = n; i >= 1; i--){ while (lastYes >= 1 && cnt[lastYes][1] <= 1 && cnt[lastYes][2] <= 1){ lastYes--; continue; } if (lastYes <= 0) break; if (cnt[i][1] == 0){ cnt[i][1]++; if (cnt[lastYes][1] > 1){ cnt[lastYes][1]--; ans += abs(i - lastYes); } else if (lastYes - 1 >= 1 && cnt[lastYes - 1][1] > 1){ cnt[lastYes - 1][1]--; ans += abs(i - lastYes) + 1; } else{ cnt[lastYes][2]--; ans += abs(i - lastYes) + 1; } i++; // for (int j = 1; j <= 2; j++){ // for (int i = 1; i <= n; i++){ // cout << cnt[i][j] << " "; // } // cout << "\n"; // } // cout << "\n\n"; continue; } if (cnt[i][2] == 0){ cnt[i][2]++; if (cnt[lastYes][2] > 1){ cnt[lastYes][2]--; ans += abs(i - lastYes); } else if (lastYes - 1 >= 1 && cnt[lastYes - 1][2] > 1){ cnt[lastYes - 1][2]--; ans += abs(i - lastYes) + 1; } else{ cnt[lastYes][1]--; ans += abs(i - lastYes) + 1; } i++; // for (int j = 1; j <= 2; j++){ // for (int i = 1; i <= n; i++){ // cout << cnt[i][j] << " "; // } // cout << "\n"; // } // cout << "\n\n"; continue; } } cout << ans << "\n"; return 0; }