using System;
using System.Linq;
using System.Collections;
using System.Collections.Generic;

class Program
{
    static void Main()
    {
        new Magatro().Solve();
    }
}

public class Magatro
{
    private int N;
    private long[] X, Y;
    private S[] Arr;

    private int[] Size;
    private int[] Par;

    private void Scan()
    {
        N = int.Parse(Console.ReadLine());
        X = new long[N];
        Y = new long[N];

        for (int i = 0; i < N; i++)
        {
            var line = Console.ReadLine().Split(' ');
            X[i] = int.Parse(line[0]);
            Y[i] = int.Parse(line[1]);
        }
    }

    private void Union(S s)
    {
        Union(s.A, s.B);
    }

    private void Union(int a, int b)
    {
        a = Root(a);
        b = Root(b);
        if (a == b) return;
        Par[b] = a;
        Size[a] += Size[b];
    }

    private bool Same(int a, int b)
    {
        return Root(a) == Root(b);
    }

    private int Root(int a)
    {
        if (Par[a] == a) return a;
        return Root(Par[a]);
    }

    public void Solve()
    {
        Scan();
        int index = 0;
        Arr = new S[(N - 1) * N / 2];
        for (int i = 0; i < N - 1; i++)
        {
            for (int j = i + 1; j < N; j++)
            {
                var dist = (X[i] - X[j]) * (X[i] - X[j]) + (Y[i] - Y[j]) * (Y[i] - Y[j]);
                Arr[index] = new S(i, j, dist);
                index++;
            }
        }

        Array.Sort(Arr, (a, b) => a.Dist.CompareTo(b.Dist));
        Size = (new int[N]).Select(i => 1).ToArray();
        Par = (new int[N]).Select((i, j) => j).ToArray();
        int ind = 0;
        for (long l = 10; true; l += 10)
        {
            long dist = l * l;
            for (int i = ind; Arr[i].Dist < dist; i++)
            {
                ind++;
                Union(Arr[i]);
                if (Same(0, N - 1))
                {
                    Console.WriteLine(l);
                    return;
                }
            }
        }
    }
}

struct S
{
    public int A, B;
    public long Dist;
    public S(int a, int b, long dist)
    {
        A = a;
        B = b;
        Dist = dist;
    }
}