Python中的list list_lst = [ ('增',), ('刪',), ('改',), ('查',), ('排序方法',), ('表達式',), ('練習',), ] 增 >>> lst = ['a', 'b', 'c'] >>> lst.append('d') >>> lst ['a' ...
list_lst = [
('增',),
('刪',),
('改',),
('查',),
('排序方法',),
('表達式',),
('練習',),
]
增
>>> lst = ['a', 'b', 'c']
>>> lst.append('d')
>>> lst
['a', 'b', 'c', 'd']
>>> lst.extend([1, 2])
>>> lst
['a', 'b', 'c', 'd', 1, 2]
刪
>>> lst = ['a', 'b', 'c']
>>>lst.pop()
'c'
>>>lst
['a', 'b']
>>>lst = ['a', 'b', 'c']
>>>lst.pop(-2)
'b'
>>>lst
['a', 'c']
>>> lst = ['a', 'b', 'c']
>>> lst.pop(1)
'b'
>>> lst
['a', 'c']
>>> lst.remove('c')
>>> lst
['a']
>>> lst.clear()
>>> lst
[]
>>> del lst
>>> lst
NameError: name 'lst' is not defined
>>>lst = ['a', 'b', 'c']
>>>del lst[1:]
>>>lst
['a']
改
>>> lst = ['a', 'b', 'c']
>>> lst[1] = 'e'
>>> lst
['a', 'e', 'c']
>>> lst = ['a', 'b', 'c']
>>> lst[1:] = 'e'
>>> lst
['a', 'e']
查
>>>lst = ['a', 'b', 'c']
>>>for i in lst:
... i
'a'
'b'
'c'
排序
>>> lst = [6, 18, 4, 7]
>>> lst.sort()
>>> lst
[4, 6, 7, 18]
>>> lst = [6, 18, 4, 7]
>>> lst.sort(reverse=True)
>>> lst
[18, 7, 6, 4]
>>> lst = [6, 18, 4, 7]
>>> lst.reverse()
>>> lst
[7, 4, 18, 6]
表達式
>>> [str(i) for i in range(2, 11)] + list('AJQK')
['2', '3', '4', '5', '6', '7', '8', '9', '10', 'A', 'J', 'Q', 'K']
練習
在不用集合的情況下,為列表去重
>>> lst = [1, 1, 2, 3, 4, 4, 4, 5]
>>> new_lst = []
>>> for i in lst:
... if i not in new_lst:
... new_lst.append(i)
...
>>> lst = new_lst
>>> lst
[1, 2, 3, 4, 5]