[Python知识库]python学习第五章习题

5-1

car = 'subaru'
print('Is car == "subaru"? I predict True')  #个人习惯优先使用单引号
print(car == 'subaru')
print('Is car == "bmw"? I predict True')
print(car == 'bmw')
print('Oops，I lose')

5-2

stra = '今天天气真好'
strb = '今天天气不好'
print(stra == strb)

stra = 'Today,I Should'
strb = 'tomrrorw,i will'
if stra != strb:
    print(stra.lower())

5-3

#aline_color = 'Red'
aline_color = 'Green'
if aline_color == 'Green':
    print('恭喜！，你杀了一个绿色的，+5分!')

5-4

#alien_color = 'Blue'
alien_color = 'Red'
if alien_color == 'Blue':
    print('恭喜！，你杀了一个蓝色的，+5分!')
else:
    print('任务失败！')

5-5

#alien_color = 'Blue'
#alien_color = 'Red'
alien_color = 'Green'
if alien_color == 'Blue':
    print('恭喜！，你杀了一个蓝色的，+5分!')
elif alien_color == 'Red':
    print('恭喜！，你杀了一个红色的，+5分!')
else:
    print('恭喜！，你杀了一个绿色的，+15分!')

5-6

age = 48
if age < 2:
    print('婴儿')
elif age < 4:
    print('幼儿')
elif age <13:
    print('儿童')
elif age < 20:
    print('青少年')
elif age < 65:
    print('成年人')
elif age > 65:
    print('老年人')

5-7

fruits = ['苹果','梨','香蕉']
str1 = '苹果'
if str1 in fruits:      #元素可以直接当条件判断
    print(f"you really like {str1}")

5-8

users = ['001','002','admin','003','004']
for user in users:
    if user == 'admin':
        print('Hello,admin!would u like to see a status report?')
    else:
        print('hello' + user + 'thank you')

5-9

#users = ['001','002','admin','003','004']
users = []
if users:   #先使用if判断列表内容是否为空，有内容为True，空的则为False
    for user in users:
        if user == 'admin':
            print('Hello,admin!would u like to see a status report?')
        else:
            print('hello' + user + 'thank you')
else:
    print('we need to find some users')

5-10-1

current_users = ['001','002','admin','003','004']
new_users = ['aaa','bbb','ccc','admin','004']
for new_user in new_users:
    if new_user in current_users:
        print(new_user + '该用户名已被使用！')
    else:
        print(new_user + '请继续，此用户名并未被使用')

5-10-2

current_users = ['aaa','BBb','ccC','admin','004']
current_users_lower = ['aaa','bbb','ccc','admin','004']
new_users = ['001','CCC','adMin','003','004']
for new_user in new_users:
    if new_user.lower() in current_users_lower:
        print(new_user + '用户名已存在！')
    else:
        print(new_user + '请继续，此用户名未被使用')