using System;

public class Program

{

    public static void Main()

    {

        int n,i,j,k,c,b=1,max1,max2,max3,max4,p;

        int[,] a;

        Console.WriteLine("n?");

        n=int.Parse(Console.ReadLine());

        a=new int[n,n];

        for(i=0;i<a.GetLength(0);i++)

        {

            for(j=0;j<a.GetLength(1);j++)

            {

                Console.WriteLine("numer?");

                a[i,j]=int.Parse(Console.ReadLine());

            }

        }

        //max1

        k=n;

        max1=a[0,1];

        if(n%2==0)c=n/2;

        else c=(n/2)+1;

        for(i=0;i<c;i++)

        {

            for(j=b;j<k-1;j++)

            {

                if(a[i,j]>max1)max1=a[i,j];

            }

            k--;

            b++;

        }

        Console.WriteLine(max1);

        //max2

        k=n;

        max2=a[1,0];

        if(n%2==0)c=n/2;

        else c=(n/2);

        for(i=1;i<k-1;i++)

        {

            for(j=0;j<c;j++)

            {

                if(a[i,j]>max2)max2=a[i,j];

            }

        }

        Console.WriteLine(max2);

        //max3

        k=n;

        b=n-1;

        if(n%2==0)c=n/2;

        else c=n/2;

        max3=a[n-1,c];

        for(i=k-1;i>=c;i--)

        {

            for(j=1;j<b;j++)

            {

                if(a[i,j]>max3)max3=a[i,j];

            }

            k--;

            b--;

​

        }

        Console.WriteLine(max3);

        //max4

        k=n;

        b=n-1;

        p=1;

        max4=a[1,n-1];

        if(n%2==0)c=n/2;

        else c=(n/2)+1;

        for(i=k-1;i>c;i--)

        {

            for(j=p;j<b;j++)

            {

                if(a[i,j]>max4)max4=a[i,j];

            }

            b--;

            p++;

        }

        Console.WriteLine(max4);

        if(max1==max2 && max1==max3 && max1==max4)Console.WriteLine("ok");

        else Console.WriteLine("not ok");

    }

}