习题26:if(如果)

发布时间:2017-11-15 14:41:25编辑:Run阅读(5321)

    练习代码如下

    # coding: utf-8
    __author__ = 'www.py3study.com'
    people = 20
    cats = 30
    dogs = 15
    if people < cats:
       print("Too many cats! The world is doomed!")
    if people > cats:
       print("Not many cats! The world is saved!")
    if people < dogs:
       print("The world is drooled on !")
    if people > dogs:
       print("The world is dry!")

    dogs += 5
    if people >= dogs:
       print("People are greater than or equal to dogs.")
    if people <= dogs:
       print("People are less than or equal to dogs.")
    if people == dogs:
       print("People are dogs.")

    应该看到的结果

    图片.png

    常见问题

    +=是什么意思?

    x += 1 和 x = x + 1一样,只是+=这种写法更省时间

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