题解 | #空心三角形图案#

while True:
    try:
        num = int(input())
        a = 1
        for i in range(num):
            if i == 0:
                print("*")
            elif i == num - 1:
                print("* " * num)
            else:
                print("*" + " " * a + "*")
                a += 2
    except:
        break