#include <iostream>
#include <algorithm>

using namespace std;
#define MAX 1000000
int main() {
    int n;
    cin >> n;

    pair<int, int> coords[n];
    for (int i = 0; i < n; i++) {
        cin >> coords[i].first >> coords[i].second;
    }

    sort(coords, coords+n);

//    for(int i = 0; i < n; i++) {
//        cout << coords[i].first << " " << coords[i].second << endl;
//    }

    //long long min = MAX, max = -MAX;

    int prev_x = coords[0].first, prev_y = coords[0].second;

    int sum = 0;

    for(int i = 1; i < n; i++) {
        sum += abs(coords[i].first - prev_x);
        sum += abs(coords[i].second - prev_y);
        prev_x = coords[i].first;
        prev_y = coords[i].second;

    }

    cout << sum << endl;

    return 0;
}