i = 1
while i <= 5:
j = 1
while j <= 5:
#end 不换行
print("*",end="")
j = j + 1
print("")
while i <= 5:
j = 1
while j <= 5:
#end 不换行
print("*",end="")
j = j + 1
print("")
i = i + 1
运行结果:
i = 1
while i <= 5:
j = 1
#关键是j <= i
while j <= i:
#end 不换行
print("*",end="")
j = j + 1
print("")
i = i + 1
运行结果: