笨办法学Python记录--习题38-40，复习前面，运用list操作函数

#习题38 区分列表和字符串，用到了split（字符串专用函数），join、append、pop（这些是list操作函数）

ten_things = "Apples Oranges Crows Telephone Liht Sugar"

print "Wait there is not 10 things in that list, let's fix that."

stuff=ten_things.split(' ')

more_stuff = ["Day","Night","Song","Frisbee","Corn","Banana","Girl","Boy"]

while len(stuff)!=10:
next_one = more_stuff.pop()
print "Adding:",next_one
stuff.append(next_one)
print "There's %d items now." % len(stuff)

print "There we go:",stuff
print "Let's do some things with stuff."

print "stuff[1]"
print stuff[1]

print "stuff[-1]"
print stuff[-1]

print "stuff.pop()"
print stuff.pop()

print "' '.join(stuff)"
print ' '.join(stuff)

print "'#'.join(stuff[3:5]"
print '#'.join(stuff[3:5]

)

 

结果：

#习题38 区分列表和字符串，同时学者使用split函数
ten_things = "Apples Oranges Crows Telephone Liht Sugar"

print "Wait there is not 10 things in that list, let's fix that."

stuff=ten_things.split(' ')

more_stuff = ["Day","Night","Song","Frisbee","Corn","Banana","Girl","Boy"]

while len(stuff)!=10:
next_one = more_stuff.pop()
print "Adding:",next_one
stuff.append(next_one)
print "There's %d items now." % len(stuff)

print "There we go:",stuff
print "Let's do some things with stuff."

print "stuff[1]"
print stuff[1]

print "stuff[-1]"
print stuff[-1]

print "stuff.pop()"
print stuff.pop()

print "' '.join(stuff)"
print ' '.join(stuff)

print "'#'.join(stuff[3:5]"
print '#'.join(stuff[3:5]

)

 

个人觉得这么使用字典很帅很帅！！

cities = {'CA':'San Francisco','MI':'Detroit','FL':'Jacksonville'}
cities['NY']='New York'
cities['OR']='Portland'

def find_city(themap,state):
    if state in themap:
        return themap[state]
    else:
        return "Not found."
        
cities['_find'] = find_city

while True:
    print "State?(ENTER to quit)",
    state = raw_input("> ")
    
    if not state:break
    city_found = cities['_find'](cities,state)
    print city_found

关于字典：字典出现在当索引不好用的时候--字典中的值并没有特殊的顺序，但是都存储在一个特定的键（key）里。key可以是数字、字符串甚至元组。

字典应用：1. 数字电话/地址簿；2. 存储文件修改次数，用文件名作为键；3. 表征游戏键盘的状态，每个键都是由坐标值组成的元组；

dict函数的使用：

>>>d=dict(name='GG', age=32)

>>>d

{'age':32,'name':'GG'}

or

>>>a=[('name','GG'),('age',42)]

>>>d=dict(a)

简单数据库实现：

people = {'Alice':{'phone':'2341','addr':'Foo drive 23'},'Beth':{'phone':'9102','addr':'Bar steet 42'},'Cecil':{'phone':'3158','addr':'Baz avenue 90'}}
labels = {'phone':'phone number','addr':'address'}
name = raw_input('Name: ')
request=raw_input('phone number(p) or address(a)?')
if request=='p':
    key = 'phone'
if request == 'a':
    key = 'addr'
if name in people:
    print "%s's %s is %s." % (name,labels[key],people[name][key])

深拷贝，浅拷贝

待续