while True: try: num = int(input()) for i in range(num): for j in range(num): print('* ' if i == 0 or j == 0 or i == num - 1 or j == num - 1 else ' ', end = '') print() except: break
while True: try: num = int(input()) for i in range(num): for j in range(num): print('* ' if i == 0 or j == 0 or i == num - 1 or j == num - 1 else ' ', end = '') print() except: break