重拾python 二十九

这一节学习下if的用法，ex29.py：

#!/usr/bin/python# -*- coding: utf-8 -*-people = 20cats = 30dogs = 15if 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 += 5if 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."

运行得到结果：

Too many cats! The world is doomed!
The world is dry!
People are greater than or equal to dogs.
People are less than or equal to dogs.
People are dogs.