#include <bits/stdc++.h>

using ll = long long;
using namespace std;




struct MinMax{
    ll x;
    ll max, min;
};

map<ll, MinMax> m;



int main() {
    ll n;

    cin >> n;

    for(int i = 0; i < n ;i++){
        ll x, y;
        cin >> x >> y;
        auto found = m.find(x);
        if(found != m.end()){
            //je tam
            found->second.max = max(found->second.max, y);
            found->second.min = min(found->second.min, y);
        }
        else{
            m.insert({x, MinMax{x,y, y}});
        }
    }

    vector<MinMax> minMax;
    for(auto & i : m) {
        minMax.emplace_back(i.second);
    }

    ll point_y = minMax[0].min;
    ll point_x = minMax[0].x;
    ll result_max = minMax[0].max - minMax[0].min;
    for(int i = 1; i < minMax.size(); i++){
        result_max += minMax[i].max - minMax[i].min;
        result_max += minMax[i].x - point_x;
        if(abs(point_y - minMax[i].max) < abs(point_y - minMax[i].min)){
            result_max += abs(point_y - minMax[i].max);
            point_y = minMax[i].min;
        }
        else{
            result_max += abs(point_y - minMax[i].min);
            point_y = minMax[i].max;
        }
        point_x = minMax[i].x;
    }

    point_y = minMax[0].max;
    point_x = minMax[0].x;
    ll result_min = minMax[0].max - minMax[0].min;
    for(int i = 1; i < minMax.size(); i++){
        result_min += minMax[i].max - minMax[i].min;
        result_min += minMax[i].x - point_x;
        if(abs(point_y - minMax[i].max) < abs(point_y - minMax[i].min)){
            result_min += abs(point_y - minMax[i].max);
            point_y = minMax[i].min;
        }
        else{
            result_min += abs(point_y - minMax[i].min);
            point_y = minMax[i].max;
        }
        point_x = minMax[i].x;
    }

    cout << min(result_max, result_min) << endl;

}