Python之if语句及条件语句

其实各个语言的基础都是相通的。

words = ['soften', 'civilize', 'personalization', 'bakery', strain', 'glimpse', 'royals']

for word in words:
    if word == 'civilize':

        print(word.upper()) #全部大写输出

    else:

        print(word.title()) #首字母大写输出

result:

Soften

CIVILIZE

Personalization

Bakery

Strain

Glimpse

Royals

*

条件语句包括：！=\<=\>=\>\<  #这点python还是做的很好哈。

chl = 21

fsy = 32

chl >=20 and fsy <=31 #检查两个条件语句，使用关键词and result:False

(chl >=20) and (fsy <=31) #也可将每个测试放在一对括号内

chl >=20 or fay <=31 #使用or result:True

*

word = ['bride', 'castle', 'masterpieces', 'mystery', 'tragedy', 'bakery', 'strain', 'glimpse']

'castle' in word #使用关键词in让python检查列表中是否有'castle'

words = ['emperor', 'castle', 'royal', 'diplomat', 'bakery', 'strain', 'glimpse']

chl = 'emperors'

if chl not in words: #if not in
    print("The word is not in words list!")

*

age = 12

if age <= 4:
    print("I like dessert and trade!")

elif age <= 18:    #python这点不一样哈，有个elif，可以有若干个elif语句

    print("I like diplomat and dumpling!")

else:

    print("I like nobility and sketch!")

result:
I like diplimat and dumpling!

*

age = 12

if age <= 4:

    price = 0

elif age <= 18:
    price = 10

else:

    price = 20

print("You admission cost is $ " + str(price) +"!") #price要str函数告诉python输出字符

**当其中一个if语句通过测试，python会跳过其他的if语句测试。

eg:寻找两个列表共同的元素（交集）

chls = ['emperor', 'nobility', 'bakery', 'sauce', 'royal']

fsys = ['emperor', 'Spring Festival', 'approaching', 'nobility']

for chl in chls:

    if chl in fsys:

        print("We can discover " + chl +"!")

    else:

        print("Oh my god! The Spring Festival is approaching, prepare " + chl + "!")

result:

We can discover emperor!

Oh my god! The Spring Festival is approaching, prepare nobility!

Oh my god! The Spring Festival is approaching, prepare bakery!

Oh my god! The Spring Festival is approaching, prepare sauce!

Oh my god! The Spring Festival is approaching, prepare royal!