How do you check if an element appears twice in a list python?

Without importing another function check if a list contains two of the same element

F.E list = [3,4,5,3] since 3 appears twice in the list return True

Thanks for the help

asked May 6, 2020 at 21:31

You can convert to set and check the resulting length:

len[set[data]] < len[data]

answered May 6, 2020 at 21:35

a_guesta_guest

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If you need to check if the element occurs exactly twice, you could do this:

l = [3,4,5,3]
if 2 in set[[l.count[n] for n in l]]:
    print['True']

answered May 6, 2020 at 21:39

ssharmassharma

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There are different approaches to solve this problem.

Solution 1: Use set[]

if len[set[]]=2 for x in lst] Will be true if at least 1 item in lst appears twice or more in string.
 
Kirill Vidov Something like this: s = 'Sololearn' l = ['a', 'o', 'l', 'r', 'n'] print[[x for x in l if s.count[x] >= 2]] # will only print 'o' and 'l'

Thank you everyone for the help
 
Kirill Vidov Show ur attempt
 
Kuba Siekierzyński
can you please help if you can?
 
Kirill Vidov Ask if you have any doubt in it a=[1,2,3,"a",5,"b",4.8] print[*[i for i in a if type[i]==type[""]]] Returns those elements from the list which are in string
 
Exactly, I would use count[] to determine if there is more than one occurence of an element in a collection.
 
Abhay if any[x in string for x in list] >= 2, but that doesn't work
 
 
  Questions : Check if an certain element appears twice in a list - Python
2022-10-02T13:15:46+00:00 2022-10-02T13:15:46+00:00
940

  

Without importing another function check if anycodings_python-3.x  a list contains
two of the same element 
F.E list = [3,4,5,3] since 3 appears twice anycodings_python-3.x  in the list return True
Thanks for the help
 Total Answers 3
31
 Answers 1 : of Check if an certain element appears twice in a list - Python
You can convert to set
and check the anycodings_list  resulting length:
len[set[data]] < len[data]
0
2022-10-02T13:15:46+00:00 2022-10-02T13:15:46+00:00Answer Link
mRahman
3
 Answers 2 : of Check if an certain element appears twice in a list - Python
If you need to check if the element anycodings_list  occurs exactly twice, you could do this:
l = [3,4,5,3]
if 2 in set[[l.count[n] for n in l]]:
    print['True']
0
2022-10-02T13:15:46+00:00 2022-10-02T13:15:46+00:00Answer Link
joy
3
 Answers 3 : of Check if an certain element appears twice in a list - Python
There are different approaches to solve anycodings_list  this problem.
Solution 1: Use set[]
if len[set[]]