using System;
public class Program
{
static void M (int n)
for (int i = 1 ; i <= n ; i++)
for (int j = 1 ; j<=n ; j++)
if (i==1 || i==n || j==1 || j==n) {
Console.Write("*"); }
else {
Console.Write(" "); }
}
Console.WriteLine();
public static void Main()
M(11);