using System;

    class Program
    {
        static void Main()
        {

            int n = int.Parse(Console.ReadLine());
            int j = 0;

            Console.WriteLine(new String('_', n / 2) + new String('*', n+2) + new String('_', n / 2));

            for(int i=1;i<n;i++)
            {
                Console.WriteLine(new String('_', n / 2) + new String('*', 1) + new String('_', n) + new String('*', 1) + new String('_', n / 2));
            }
            for(int i=1;i<=(n/2)+1;i++)
            {
                Console.WriteLine(new String('_', (n / 2)-i+1) + new String('*', 1+j) + new String('_', n-j ) + new String('*', 1+j) + new String('_', (n / 2)-i+1));
                j+=2;
            }
            for(int i=1;i<=n/2;i++)
            {
                Console.WriteLine(new String('_', i) + new String('*', n - 2 * i) + new String('_', 1 + 2 * i) + new String('*', n - 2 * i) + new String('_', i));
                j += 2;
            }
        }
    }