#include<bits/stdc++.h>

using namespace std;

int main(){
    int n;
    cin >> n;

    vector< pair<int,int> > v;

    for(int i = 0; i < n; i++){
        int x,y;
        cin >> x >> y;
        v.push_back(make_pair(x,y));
    }
    sort(v.begin(), v.end());

    int sum = 0;
    int prev_x = v[0].first;
    int prev_y = v[0].second;

    for(int i = 1; i < v.size(); i++){
        sum += abs(prev_x - v[i].first);
        sum += abs(prev_y - v[i].second);
        prev_x = v[i].first;
        prev_y = v[i].second;
    }
    cout << sum << endl;
}