参考链接： Python while循环
真的脑子越学越乱，得好好抽出一个时间来好好地理理思路和学习的内容，还好这个笔记比较好弄 弄完预习预习 好好整理一下脑子 猜拳游戏 if 循环
import random
computer = random.randint(1, 3)
player = int(input("请输入您的状态代号，石头请输：1、剪子请输：2、布请输：3: "))
if ((player == 1) and (computer == 2)) or ((player == 2) and (computer == 3)) or ((player == 3)
and (computer == 1)):
print("你赢了")
elif (player == computer):
print("平局")
else:
print("你输了")
while–循环
import random
while True:
computer = random.randint(1, 3)
player = int(input("请输入您的状态代号，石头请输：1、剪子请输：2、布请输：3: "))
if ((player == 1) and (computer == 2)) or ((player == 2) and (computer == 3)) or ((player == 3)
and (computer == 1)):
print("你赢了")
elif (player == computer):
print("平局")
elif((player == 1) and (computer == 3)) or ((player == 2) and (computer == 1)) or ((player == 3)
and (computer == 2)):
print("你输了")
else:
print("请输入数字1或2或3，您输入的 %d 不正确" % player)
break：用来中断循环
continue: 用来跳出本次循环，直接开始下一次循环。 在使用关键字之前，需要确认循环的计数是否修改， 否则可能会导致死循环
while 循环嵌套 i = 1 while i < 3:
# 被嵌套的循环
j = 1
while j < 5:
print(f'{i} --- {j}')
# break
continue
j = 1
i = 1
打印： * ** *** **** *****
第一种方法
# while 循环
# i = 1
# while i <= 5:
# print("*" * i)
# i =1
# while 嵌套循环
# i = 1
# while i <= 5:
# j = 1
# while j <= i:
# print("*", end = "")
# j = 1
# print()
# i = 1
打印： ：* * * * * ：* * * * * ：* * * * * ：* * * * * ：* * * * *
i = 1
# while i <= 5:
# j = 1
# while j <= 5:
# print("*", end = "")
# j = 1
# print()
# i = 1
九九乘法表
i = 1
while i <= 9:
j = 1
while j <= i:
print("%d * %d = %-3d " % (j,i,j * i), end = " ")
j = 1
print()
i = 1
for-in 循环使用方式
def test_func1():
#得到字符串中的所有字符
for c in 'abcdefg':
# 将小写字母变成大写输出
print(c.upper())
test_func1()
for-in 循环如果需要计数，需要配合 range() 实现 range 有两个参数，参数一是起始值 ，参数二是终止值 得到一个数字区间，是一个左闭右开区间， [start, end) 如果只给一个参数，那么默认是终止值 ，起始值默认是 0
def test_func2():
for i in range(10, 20):
print(i)
test_func2()
def test_func3():
# 如果需 要计数，但又不需 要用到这个数字时，可以没有循环变量
for _ in range(5):
print('hello', _)
test_func3()
