我如何检查一个列表是否有任何重复,并返回一个没有重复的新列表?
当前回答
Python 3中非常简单的方法:
>>> n = [1, 2, 3, 4, 1, 1]
>>> n
[1, 2, 3, 4, 1, 1]
>>> m = sorted(list(set(n)))
>>> m
[1, 2, 3, 4]
其他回答
Write a Python program to create a list of numbers by taking input from the user and then remove the duplicates from the list. You can take input of non-zero numbers, with an appropriate prompt, from the user until the user enters a zero to create the list assuming that the numbers are non-zero.
Sample Input: [10, 34, 18, 10, 12, 34, 18, 20, 25, 20]
Output: [10, 34, 18, 12, 20, 25]
lst = []
print("ENTER ZERO NUMBER FOR EXIT !!!!!!!!!!!!")
print("ENTER LIST ELEMENTS :: ")
while True:
n = int(input())
if n == 0 :
print("!!!!!!!!!!! EXIT !!!!!!!!!!!!")
break
else :
lst.append(n)
print("LIST ELEMENR ARE :: ",lst)
#dup = set()
uniq = []
for x in lst:
if x not in uniq:
uniq.append(x)
# dup.add(x)
print("UNIQUE ELEMENTS IN LIST ARE :: ",uniq)
如果你想保持顺序,不使用任何外部模块,这里有一个简单的方法:
>>> t = [1, 9, 2, 3, 4, 5, 3, 6, 7, 5, 8, 9]
>>> list(dict.fromkeys(t))
[1, 9, 2, 3, 4, 5, 6, 7, 8]
注意:这种方法保留了出现的顺序,因此,如上所示,9将在1之后,因为它是第一次出现。然而,这和你做的结果是一样的
from collections import OrderedDict
ulist=list(OrderedDict.fromkeys(l))
但它更短,跑得更快。
这是因为每次fromkeys函数尝试创建一个新键时,如果值已经存在,它就会简单地覆盖它。然而,这不会影响字典,因为fromkeys创建的字典中所有键的值都为None,因此有效地消除了所有重复的值。
您可以使用以下函数:
def rem_dupes(dup_list):
yooneeks = []
for elem in dup_list:
if elem not in yooneeks:
yooneeks.append(elem)
return yooneeks
例子:
my_list = ['this','is','a','list','with','dupicates','in', 'the', 'list']
用法:
rem_dupes(my_list)
[‘这个’,‘是’,‘“,“列表”,“与”,“dupicates”,“在”,“的”)
你可以使用set来删除重复项:
mylist = list(set(mylist))
但请注意,结果将是无序的。如果这是个问题的话:
mylist.sort()
我没有看到非哈希值的答案,一行,nlog n,标准库,所以这是我的答案:
list(map(operator.itemgetter(0), itertools.groupby(sorted(items))))
或作为一个生成函数:
def unique(items: Iterable[T]) -> Iterable[T]:
"""For unhashable items (can't use set to unique) with a partial order"""
yield from map(operator.itemgetter(0), itertools.groupby(sorted(items)))