#include <iostream>
#include <vector>
#include <algorithm>

struct Coord {
    int x;
    int y;
};

bool compareCoords(const Coord &lhs, const Coord &rhs) {
    if (lhs.x < rhs.x)
        return true;
    if (lhs.x > rhs.x)
        return false;
    return lhs.y < rhs.y;
}

struct PointDistance {
    int y = 0;
    long long d = 0;
};

int main() {
    int N;
    std::cin >> N;
    std::vector<Coord> coords(N);
    for (int i = 0; i < N; ++i) {
        std::cin >> coords[i].x >> coords[i].y;
    }

    std::sort(coords.begin(), coords.end(), compareCoords);

    long long distance = coords.back().x - coords.front().x;

    PointDistance last_low, last_high;
    int current_x = coords[0].x;
    bool first_iter = true;
    for (int i = 0; i < N;) {
        PointDistance low, high;
        low.y = high.y = coords[i].y;
        while (i < N && coords[i].x == current_x) {
            low.y = std::min(low.y, coords[i].y);
            high.y = std::max(high.y, coords[i].y);
            ++i;
        }
        distance += (high.y - low.y);

        if (first_iter) {
            last_low.y = low.y;
            last_high.y = high.y;
            first_iter = false;
        }

        low.d = std::min(last_low.d + abs(high.y - last_low.y),
                         last_high.d + abs(high.y - last_high.y));
        high.d = std::min(last_low.d + abs(low.y - last_low.y),
                          last_high.d + abs(low.y - last_high.y));
        last_low = low;
        last_high = high;
        if (i < N)
            current_x = coords[i].x;
    }

    distance += std::min(last_low.d, last_high.d);
    std::cout << distance << '\n';

    return 0;
}