Python 图案打印--圣诞树

# 提示用户需要打印的层数
layer = int(input("请输入需要打印的层数： "))

for i in range(1, layer + 1):
  space_num = layer - i
  start_num = 2 * i -1
  for j in range(space_num):
    print(" ",end="")
  for j in range(start_num):
    print("*",end="")
  print()

for i in range(layer + 1):
  for j in range((2 * layer - 1) // 2):

    print(" ",end = "")
  print("*")