14天Python编程从入门到实践--Day7：if语句

#5.2
print("car" == "car ")  #False
print("car" == "car")   #True
print("car" == "Car".lower())   #True
print((10-3) == 7)  #True
print((10-3) != 8)  #True
print(10 > 3)   #True
print(10 >= 13) #False
print(10 >3 and 3 >3) #False
print(10 >3 or 3 >3)  #True

lst = ['a',3,'哈哈']
lst1 = 3
print(lst1 in lst)  #True
print('哈哈' not in lst)  #False

#5.3#1
alien_color = "green"
if alien_color == "green":
    print("恭喜你获得了5点！")

#5.4#2
alien_color = "yellow"
if alien_color == "green":
    print("射杀绿色外星人获得5点！")
else:
    print("射杀高级外星人获得10点！")

#5.5#3
if alien_color == "green":
    print("射杀绿色外星人获得5点！")
elif alien_color =="yellow":
    print("射杀黄色外星人获得10点！")
else:
    print("射杀高级外星人获得15点！")
    
#5.6
age = 10
if age < 2:
    print("婴儿")
elif age >= 2 and age < 4:
    print("蹒跚学步")
elif age >= 4 and age < 13:
    print("儿童")
elif age >= 13 and age < 20:
    print("青少年")
elif age >= 20 and age < 65:
    print("成年人")
else:
    print("老年人")
    
#5.7
favorite_fruits = ["猕猴桃","苹果","西瓜"]
if "苹果" in favorite_fruits:
    print("你真的好喜欢苹果呀！")
if "黄瓜" in favorite_fruits:
    print("你真的好喜欢黄瓜呀！")
if "猕猴桃" in favorite_fruits:
    print("你真的好喜欢猕猴桃呀！")
~~~~~~~~~~~~~~~~~~~~~~~~~~
False
True
True
True
True
True
False
False
True
True
False
恭喜你获得了5点！
射杀高级外星人获得10点！
射杀黄色外星人获得10点！
儿童
你真的好喜欢苹果呀！
你真的好喜欢猕猴桃呀！

#5.8
users = ["admin","Jack","波哥","波妞","大青"]
for user in users:
    if user == "admin":
        print("你好" + "管理员，" + "您是否需要看一看状态报告？")
    else:
        print("你好" + user + "欢迎回来！")

#5.9
users = []
if not users:
    print("没有用户啊")
    
for user in users:
    if user == "admin":
        print("你好" + "管理员，" + "您是否需要看一看状态报告？")
    else:
        print("你好" + user + "欢迎回来！")

#5.10
current_users = ["boGe","波妞","大青","想飞","李白"]
new_users = ["Boge","啊啊","嗯嗯","啊哈","李白"]

for new_user in new_users:
    #下面这种创建列表的方式为列表推导式（列表解析式）
    if new_user.lower() in [current_user.lower() for current_user in current_users]:
        print(new_user +"这个用户名已经存在，请重新起个名字")
    else:
        print(new_user + "未被使用")

#5.11
nums = [i for i in range(1,10)]
for num in nums:
    if num == 1:
        print("1st")
    elif num == 2:
        print("2nd")
    elif num == 3:
        print("3rd")
    else:
        print(str(num) + "th")
~~~~~~~~~~~~~~~~~~~~~~~
你好管理员，您是否需要看一看状态报告？
你好Jack欢迎回来！
你好波哥欢迎回来！
你好波妞欢迎回来！
你好大青欢迎回来！
没有用户啊
Boge这个用户名已经存在，请重新起个名字
啊啊未被使用
嗯嗯未被使用
啊哈未被使用
李白这个用户名已经存在，请重新起个名字
1st
2nd
3rd
4th
5th
6th
7th
8th
9th