列表和字典嵌套

zd = {
    'shen': ['python','java','ruby'],
    'yuan': ['java'],
    'chen': ['c++'],
    'long': ['delphi'],
    'huge': ['ruby'],
  }

for k,v in zd.items():     #同时遍历键和值用item方法， 同时 遍历 键 和 值
    print('\n'+k)
    for i in v:
        print(i)

print('------------------------------------------------')

for k in zd.keys():            #遍历字典所有的  键
    print(k)


print('------------------------------------------------')

for i in zd.values():           #遍历字典的   值
    print(i)

print('+++++++++++')

for i in zd:                   #遍历字典的   值
    print(zd[i])

print('------------------------------------------------')

print(zd.items())

ssx = list(zd.items())

print(ssx[0])
print(ssx[1])

print('+++++++++++++++++++++++++')

for i in ssx:
    print(i)


print('------------------------------------------------')

print(zd.values())         #打印字典的值，为一个列表      返回一个值的列表而不包含任何键

sx = list(zd.values())      #list使之成为一个列表

print(sx)

print('+++++++++++++++')

print(sx[0])

print('------------------------------------------------')

print(zd.keys())    #返回一个所有键的列表    即返还的是一个列表，包含所有键

cp = []

cp = zd.keys()

for i in cp:
    print(i)


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执行结果：


shen
python
java
ruby

yuan
java

chen
c++

long
delphi

huge
ruby

------------------------------------------------

shen
yuan
chen
long
huge

------------------------------------------------

['python', 'java', 'ruby']
['java']
['c++']
['delphi']
['ruby']

+++++++++++

['python', 'java', 'ruby']
['java']
['c++']
['delphi']
['ruby']

------------------------------------------------

dict_items([('shen', ['python', 'java', 'ruby']), ('yuan', ['java']), ('chen', ['c++']), ('long', ['delphi']), ('huge', ['ruby'])])
('shen', ['python', 'java', 'ruby'])
('yuan', ['java'])

+++++++++++++++++++++++++

('shen', ['python', 'java', 'ruby'])
('yuan', ['java'])
('chen', ['c++'])
('long', ['delphi'])
('huge', ['ruby'])

------------------------------------------------

dict_values([['python', 'java', 'ruby'], ['java'], ['c++'], ['delphi'], ['ruby']])
[['python', 'java', 'ruby'], ['java'], ['c++'], ['delphi'], ['ruby']]

+++++++++++++++

['python', 'java', 'ruby']

------------------------------------------------

dict_keys(['shen', 'yuan', 'chen', 'long', 'huge'])
shen
yuan
chen
long
huge

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list1 = ['key1','key2','key3']

list2 = ['1','2','3']                #用zip函数合并


lb = list(zip(list1,list2))                #返回列表

print(lb)

#----------------------------------------------------

zd = {}

zd = dict(zip(list1,list2))        #返回字典

print(zd)

+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

执行结果：

[('key1', '1'), ('key2', '2'), ('key3', '3')]


{'key1': '1', 'key2': '2', 'key3': '3'}


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将列表转换为字典：


new_list= [['key1','value1'],['key2','value2'],['key3','value3']]

zd = {}

zd  = dict(new_list)

print(zd)


执行结果：


{'key1': 'value1', 'key2': 'value2', 'key3': 'value3'}


=================================================================================

方法二：


new_list= [['key1','value1'],['key2','value2'],['key3','value3']]

new_dict = {}

for i in new_list:
    print(i)               #  i 为 ：['key1','value1']
    new_dict[i[0]] = i[1]   # i[1]为 ：value1                 左边key  右边value
    
                          #i[0] 为：  key1
# new_dict[key1] = value1    #为增加k、v值

print(new_dict)


执行结果：


['key1', 'value1']
['key2', 'value2']
['key3', 'value3']
{'key1': 'value1', 'key2': 'value2', 'key3': 'value3'}