#include <bits/stdc++.h>
using namespace std;

#define int long long
typedef pair<int, int> ii;
typedef vector<ii> vii;

#define x first
#define y second

#define f(i,a,b) for(int i = (a); i < (b); ++i)

int ab(int x) {
    return x > 0 ? x : -x;
}

int dst(int x, int y) {
    return ab(x-y);
}

signed main() {
    ios_base::sync_with_stdio(0);
    int n;
    cin >> n;
    vii v(n);
    for (int i=0; i < n; ++i) {
        cin >> v[i].x >> v[i].y;
    }

    sort(v.begin(), v.end());
    int bot_y = v[0].y;
    int top_y = v[0].y;
    int bot_d = 0;
    int top_d = 0;

    for (int i=0; i < n; ++i) {
        if (v[i].x == v[0].x) {
            top_y = v[i].y;
        }
    }

    for (int i=0; i < n; ++i) {
        int j = i;
        while(j < n && v[i].x == v[j].x) j++;
        j--;

        int ntd = min(bot_d+ dst(bot_y, v[i].y)+dst(v[i].y, v[j].y), top_d+dst(top_y, v[i].y) + dst(v[i].y, v[j].y));
        int nbd = min(top_d+dst(top_y, v[j].y), bot_d+dst(bot_y, v[j].y)) + dst(v[i].y, v[j].y);

        bot_d = nbd;
        top_d = ntd;
        bot_y = v[i].y;
        top_y = v[j].y;
        i = j;
    }

    cout << min(bot_d, top_d) + v[n-1].x-v[0].x << endl;
}