#include<bits/stdc++.h>

using namespace std;

#define MAXN 200000

struct info {

        int id,x,y;

} a[MAXN+];

int N,i;

int dist[MAXN+];

vector< pair<int,int> > E[MAXN+];

template <typename T> inline void read(T &x) {

        int f = ; x = ;

        char c = getchar();

        for (; !isdigit(c); c = getchar()) { if (c == '-') f = -f; }

        for (; isdigit(c);  c = getchar()) x = (x << ) + (x << ) + c - '';

        x *= f;

}

template <typename T> inline void write(T x) {

        if (x < ) { putchar('-'); x = -x; }

        if (x > ) write(x/);

        putchar(x%+'');

}

template <typename T> inline void writeln(T x) {

        write(x);

        puts("");

}

inline bool cmp1(info a,info b) { return a.x < b.x; }

inline bool cmp2(info a,info b) { return a.y < b.y; }

inline void add_edge(int x,int y,int d) {

        E[x].push_back(make_pair(y,d));

        E[y].push_back(make_pair(x,d));

}

inline void dijkstra() {

        int i,x,to,cost;

        static int vis[MAXN+];

        priority_queue< pair<int,int> > q;

        for (i = ; i <= N; i++) dist[i] = INT_MAX;

        q.push(make_pair(,));

        while (!q.empty()) {

                x = q.top().second; q.pop();

                if (vis[x]) continue;

                for (i = ; i < E[x].size(); i++) {

                        to = E[x][i].first;

                        cost = E[x][i].second;

                        if (dist[x] + cost < dist[to]) {

                                dist[to] = dist[x] + cost;

                                q.push(make_pair(-dist[to],to));

                        }

                }

        }

}

int main() {

        read(N);

        for (i = ; i <= N; i++) {

                read(a[i].x); read(a[i].y);

                a[i].id = i;

        }

        sort(a+,a+N+,cmp1);

        for (i = ; i <= N; i++) add_edge(a[i-].id,a[i].id,a[i].x-a[i-].x);

        sort(a+,a+N+,cmp2);

        for (i = ; i <= N; i++) add_edge(a[i-].id,a[i].id,a[i].y-a[i-].y);

        dijkstra();

        writeln(dist[N]);

        return ;

}