python之中用while循环打出四种星星形状

• 第一种：

*
**
***
****
*****

i = 1
while i <= 5:
    j = 1
    while j <= i:
        print("*",end='')     # 不换行输出
        j += 1
    print()   #手动换行
    i += 1

• 第二种

    *
   **
  ***
 ****
*****

i =1
while i <= 5:
    j = 1
    while j <= (5 - i):
        print(" ",end='')
        j += 1
    while (j >(5-i) and j <= 5):
        print("*",end='')
        j += 1
    print()
    i += 1

• 第三种：

*****
****
***
**
*

i = 5
while i >= 0:
    j = 1
    while j <= i:
        print("*",end='')
        j += 1
    print()
    i -= 1

• 第四种：

*****
 ****
  ***
   **
    *

i = 1
while i <= 5:
    j = 1
    while j < i:
        print(" ",end='')
        j += 1
    while j >= i and j <= 5:
        print("*",end='')
        j += 1
    print()
    i += 1