/*
Author: Nguyen Chi Thanh - High School for the Gifted - VNU.HCM (i2528)
*/
#include <bits/stdc++.h>
using namespace std;
#define int long long
#define ull unsigned long long
#define ld long double
#define pii pair<int, int>
#define fi first
#define se second
#define __builtin_popcount __builtin_popcountll
#define all(x) (x).begin(), (x).end()
#define BIT(x, i) (((x) >> (i)) & 1)
#define MASK(x) ((1ll << (x)))
#define debug(a, l, r) for (int _i = (l); _i <= (r); ++_i) cout << (a)[_i] << ' '; cout << '\n';
const int MAXN = 1e5 + 5;
const int INF = 1e18 + 5;
int n;
pii coins[MAXN];
void init() {
cin >> n;
for (int i = 1; i <= 2 * n; ++i)
cin >> coins[i].fi >> coins[i].se;
}
namespace subtask1 {
bool check() {return n <= 10;}
void solve() {
vector<pii> des(2 * n + 5);
for (int i = 1; i <= n; ++i) des[i] = {i, 1};
for (int i = 1; i <= n; ++i) des[i + n] = {i, 2};
n = 2 * n; // For easier implementation
vector<vector<int>> dp(MASK(n) + 5, vector<int>(n + 5, INF));
auto dist = [&] (pii &x, pii &y) {
return abs(x.fi - y.fi) + abs(x.se - y.se);
};
for (int mask = 0; mask < MASK(n); ++mask) {
for (int i = 0; i < n; ++i) {
if (!BIT(mask, i)) continue;
if (__builtin_popcount(mask) == 1) {
dp[mask][i] = dist(coins[i + 1], des[1]);
continue;
}
int lst = __builtin_popcount(mask);
int pmask = mask ^ MASK(i);
int best = INF;
for (int j = 0; j < n; ++j) {
if (!BIT(pmask, j)) continue;
best = min(best, dp[pmask][j]);
}
if (best < INF)
dp[mask][i] = best + dist(coins[i + 1], des[lst]);
}
}
int res = INF;
for (int i = 0; i < n; ++i) res = min(res, dp[MASK(n) - 1][i]);
cout << res;
}
}
signed main() {
#ifdef NCTHANH
freopen("input.txt", "r", stdin);
freopen("output.txt", "w", stdout);
#endif
ios_base::sync_with_stdio(0);
cin.tie(nullptr); cout.tie(nullptr);
init();
if (subtask1::check()) return subtask1::solve(), 0;
return 0;
}
