#include <iostream>
using namespace std;
int main()
{
    int n;
    cin >> n;
    for (int i=0; i<n; i++)
    {
        for (int j=0; j<n; j++)
        {
            if (i==0 || i==n-1 || j==0 || j==n-1)
            {
                cout << "*";
            }
            else
            {
                cout << " ";
            }
        }
        cout << endl;
    }
    return 0;
}