变量是用来指代某种东西(字符串, 数字, 函数等等)的名字. 好的变量名可以让程序更加容易理解.
cars = 100
space_in_a_car = 4.0
drivers = 30
passengers = 90
cars_not_driven = cars - drivers
cars_driven = drivers
carpool_capacity = cars_driven * space_in_a_car
average_passengers_per_car = passengers / cars_driven
print "There are", cars, "cars avaiable."
print "There are only", drivers, "drivers avaiable."
print "There will be", cars_not_driven, "empty cars today."
print "We can transport", carpool_capacity, "people today."
print "We have", passengers, "to carpool today."
print "We need to put about", average_passengers_per_car, "in each car."
There are 100 cars avaiable. There are only 30 drivers avaiable. There will be 70 empty cars today. We can transport 120.0 people today. We have 90 to carpool today. We need to put about 3 in each car.
=
两边的空格.print "Hey %s there." % "you"
Hey you there.