#include <iostream>
#include <vector>
#include <cmath>
#include <algorithm>
#include <deque>
#include <map>
#include <set>
#include <complex>
#include <string>
#include <unordered_map>
#include <unordered_set>
#include <random>
#define ft first
#define sc second
#define pb push_back
#define len(v) (int)v.size()
#define int ll
using namespace std;
typedef long long ll;
int sgn(int x) {
if(x < 0)
return -1;
if(x == 0)
return 0;
return 1;
}
signed main() {
#ifdef PC
freopen("in.txt", "r", stdin);
freopen("out.txt", "w", stdout);
#endif
ios_base::sync_with_stdio(0);
cin.tie(0);
cout.tie(0);
int n;
cin >> n;
vector<vector<int>> have(n, vector<int> (2, 0));
int ans = 0;
for (int i = 0; i < 2 * n; i++) {
int x, y;
cin >> x >> y;
if(y < 1)
ans += (1 - y), y = 1;
if(y > 2)
ans += (y - 2), y = 2;
if(x < 1)
ans += (1 - x), x = 1;
if(x > n)
ans += (x - n), x = n;
have[x - 1][y - 1]++;
}
// for (int j = 0; j < 2; j++) {
// for (int i = 0; i < n; i++) {
// cout << have[i][j] << " ";
// }
// cout << endl;
// }
// cout << ans << endl;
// ans = 0;
int top = 0, down = 0;
for (int i = 0; i < n; i++) {
top += have[i][0], down += have[i][1];
top--, down--;
// cout << i << " " << ans << " " << top << " " << down << endl;
if(top * down < 0) {
int per = min(abs(top), abs(down));
top += -1 * sgn(top) * per;
down += -1 * sgn(down) * per;
ans += per;
}
ans += abs(top) + abs(down);
}
cout << ans << '\n';
}
/*
if(have[i][0] == 0) {
for (int j = i + 1; j < n; j++) {
if(have[j][0] > 1) {
cout << "X " << i << " " << j << endl;
have[j][0]--;
ans += (j - i);
have[i][0] = 1;
break;
}
if(j == i + 1 && down != 0) {
down--;
ans += 1;
have[i][0] = 1;
break;
}
if(have[j - 1][1] > 1) {
have[j - 1][1]--;
ans += (j - i);
have[i][0] = 1;
break;
}
}
if(have[i][0] == 0) {
ans += (n - i);
have[i][0] = 1;
if(i != n - 1)
have[n - 1][1]--;
}
}
if(have[i][1] == 0) {
for (int j = i + 1; j < n; j++) {
if(have[j][1] > 1) {
have[j][1]--;
ans += (j - i);
have[i][1] = 1;
break;
}
if(j == i + 1 && top != 0) {
top--;
ans += 1;
have[i][1] = 1;
break;
}
if(have[j - 1][0] > 1) {
have[j - 1][0]--;
ans += (j - i);
have[i][1] = 1;
break;
}
}
if(have[i][1] == 0) {
have[i][1] = 1;
ans += (n - i);
if(i != n - 1)
have[n - 1][0]--;
}
}
if(i == n - 1)
break;
ans += top + down;
}
*/
