Delete duplicates of a list whithout using using a secondary list












-5















I have an exercise for my homeworks where I need to write a program that takes a list of integers as input, and returns the same list without any duplicate numbers.
The first idea that came to my mind is a loop using another list to compare with the first one, but we are not allowed to use another list.






python







share|improve this question




















  • 1





    Well, if you are not allowed to use auxiliary storage, you are going to have to rely on mutator methods like .remove or del my_list[i] Try something then ask a question if you run into problems, providing your Minimal, Complete, and Verifiable example. Otherwise, this is too broad.

    – juanpa.arrivillaga
    Nov 22 '18 at 17:11








  • 1





    Hey! Welcome to StackOverflow. Right now, your question is kinda generic, since we have no idea of what you've tried so far. I highly recomend you post your attempts so far. Also, this can be useful for asking about homework: meta.stackoverflow.com/questions/334822/…

    – Helena Martins
    Nov 22 '18 at 17:13











  • Note, your first instinct was on the right track, but generally you would use a set as auxilliary storage in this case, because then you can remove duplicate in linear time!

    – juanpa.arrivillaga
    Nov 22 '18 at 17:14











  • Thank's for your answers, It finally worked perfectly with list(set()) . Pretty sure that's not what my teachers wanted me to do, since they always want us to use math with ugly loops instead of built-in fonctions (which is kinda stupid in my opinion) but anyway thank you!

    – Axel
    Nov 22 '18 at 18:16
















-5















I have an exercise for my homeworks where I need to write a program that takes a list of integers as input, and returns the same list without any duplicate numbers.
The first idea that came to my mind is a loop using another list to compare with the first one, but we are not allowed to use another list.






python







share|improve this question




















  • 1





    Well, if you are not allowed to use auxiliary storage, you are going to have to rely on mutator methods like .remove or del my_list[i] Try something then ask a question if you run into problems, providing your Minimal, Complete, and Verifiable example. Otherwise, this is too broad.

    – juanpa.arrivillaga
    Nov 22 '18 at 17:11








  • 1





    Hey! Welcome to StackOverflow. Right now, your question is kinda generic, since we have no idea of what you've tried so far. I highly recomend you post your attempts so far. Also, this can be useful for asking about homework: meta.stackoverflow.com/questions/334822/…

    – Helena Martins
    Nov 22 '18 at 17:13











  • Note, your first instinct was on the right track, but generally you would use a set as auxilliary storage in this case, because then you can remove duplicate in linear time!

    – juanpa.arrivillaga
    Nov 22 '18 at 17:14











  • Thank's for your answers, It finally worked perfectly with list(set()) . Pretty sure that's not what my teachers wanted me to do, since they always want us to use math with ugly loops instead of built-in fonctions (which is kinda stupid in my opinion) but anyway thank you!

    – Axel
    Nov 22 '18 at 18:16














-5












-5








-5








I have an exercise for my homeworks where I need to write a program that takes a list of integers as input, and returns the same list without any duplicate numbers.
The first idea that came to my mind is a loop using another list to compare with the first one, but we are not allowed to use another list.






python







share|improve this question
















I have an exercise for my homeworks where I need to write a program that takes a list of integers as input, and returns the same list without any duplicate numbers.
The first idea that came to my mind is a loop using another list to compare with the first one, but we are not allowed to use another list.






python




python






share|improve this question















share|improve this question













share|improve this question




share|improve this question








edited Nov 22 '18 at 19:29









Aravind Bhat K

274214




274214










asked Nov 22 '18 at 17:08









Axel Axel

1




1








  • 1





    Well, if you are not allowed to use auxiliary storage, you are going to have to rely on mutator methods like .remove or del my_list[i] Try something then ask a question if you run into problems, providing your Minimal, Complete, and Verifiable example. Otherwise, this is too broad.

    – juanpa.arrivillaga
    Nov 22 '18 at 17:11








  • 1





    Hey! Welcome to StackOverflow. Right now, your question is kinda generic, since we have no idea of what you've tried so far. I highly recomend you post your attempts so far. Also, this can be useful for asking about homework: meta.stackoverflow.com/questions/334822/…

    – Helena Martins
    Nov 22 '18 at 17:13











  • Note, your first instinct was on the right track, but generally you would use a set as auxilliary storage in this case, because then you can remove duplicate in linear time!

    – juanpa.arrivillaga
    Nov 22 '18 at 17:14











  • Thank's for your answers, It finally worked perfectly with list(set()) . Pretty sure that's not what my teachers wanted me to do, since they always want us to use math with ugly loops instead of built-in fonctions (which is kinda stupid in my opinion) but anyway thank you!

    – Axel
    Nov 22 '18 at 18:16














  • 1





    Well, if you are not allowed to use auxiliary storage, you are going to have to rely on mutator methods like .remove or del my_list[i] Try something then ask a question if you run into problems, providing your Minimal, Complete, and Verifiable example. Otherwise, this is too broad.

    – juanpa.arrivillaga
    Nov 22 '18 at 17:11








  • 1





    Hey! Welcome to StackOverflow. Right now, your question is kinda generic, since we have no idea of what you've tried so far. I highly recomend you post your attempts so far. Also, this can be useful for asking about homework: meta.stackoverflow.com/questions/334822/…

    – Helena Martins
    Nov 22 '18 at 17:13











  • Note, your first instinct was on the right track, but generally you would use a set as auxilliary storage in this case, because then you can remove duplicate in linear time!

    – juanpa.arrivillaga
    Nov 22 '18 at 17:14











  • Thank's for your answers, It finally worked perfectly with list(set()) . Pretty sure that's not what my teachers wanted me to do, since they always want us to use math with ugly loops instead of built-in fonctions (which is kinda stupid in my opinion) but anyway thank you!

    – Axel
    Nov 22 '18 at 18:16








1




1





Well, if you are not allowed to use auxiliary storage, you are going to have to rely on mutator methods like .remove or del my_list[i] Try something then ask a question if you run into problems, providing your Minimal, Complete, and Verifiable example. Otherwise, this is too broad.

– juanpa.arrivillaga
Nov 22 '18 at 17:11







Well, if you are not allowed to use auxiliary storage, you are going to have to rely on mutator methods like .remove or del my_list[i] Try something then ask a question if you run into problems, providing your Minimal, Complete, and Verifiable example. Otherwise, this is too broad.

– juanpa.arrivillaga
Nov 22 '18 at 17:11






1




1





Hey! Welcome to StackOverflow. Right now, your question is kinda generic, since we have no idea of what you've tried so far. I highly recomend you post your attempts so far. Also, this can be useful for asking about homework: meta.stackoverflow.com/questions/334822/…

– Helena Martins
Nov 22 '18 at 17:13





Hey! Welcome to StackOverflow. Right now, your question is kinda generic, since we have no idea of what you've tried so far. I highly recomend you post your attempts so far. Also, this can be useful for asking about homework: meta.stackoverflow.com/questions/334822/…

– Helena Martins
Nov 22 '18 at 17:13













Note, your first instinct was on the right track, but generally you would use a set as auxilliary storage in this case, because then you can remove duplicate in linear time!

– juanpa.arrivillaga
Nov 22 '18 at 17:14





Note, your first instinct was on the right track, but generally you would use a set as auxilliary storage in this case, because then you can remove duplicate in linear time!

– juanpa.arrivillaga
Nov 22 '18 at 17:14













Thank's for your answers, It finally worked perfectly with list(set()) . Pretty sure that's not what my teachers wanted me to do, since they always want us to use math with ugly loops instead of built-in fonctions (which is kinda stupid in my opinion) but anyway thank you!

– Axel
Nov 22 '18 at 18:16





Thank's for your answers, It finally worked perfectly with list(set()) . Pretty sure that's not what my teachers wanted me to do, since they always want us to use math with ugly loops instead of built-in fonctions (which is kinda stupid in my opinion) but anyway thank you!

– Axel
Nov 22 '18 at 18:16












2 Answers
2






active

oldest

votes


















-1














You can use set



s=['a', 'b', 'c', 'd', 'a']

s=list(set(s))

print(s)

>>> ['b', 'c', 'd', 'a']


Well, as for the comments, you can use OrderedDict



from collections import OrderedDict

s=['a', 'b', 'c', 'd', 'a']

print(list(OrderedDict.fromkeys(s)))





share|improve this answer





















  • 1





    I imagine if you are not allowed to use another list you are not allowed to use a set, but even if you were, this would then become a clear duplicate.

    – juanpa.arrivillaga
    Nov 22 '18 at 17:13






  • 2





    This solution uses, even if implicitly, another list. :-)

    – Sidon
    Nov 22 '18 at 17:16





















-1














You can cast the list to a set and the cast that back to a list.



l = [1, 1, 2, 2, 3]

s = set(l)

list_without_duplicates = list(s)





share|improve this answer























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    2 Answers
    2






    active

    oldest

    votes








    2 Answers
    2






    active

    oldest

    votes









    active

    oldest

    votes






    active

    oldest

    votes









    -1














    You can use set



    s=['a', 'b', 'c', 'd', 'a']
    
s=list(set(s))
    
print(s)
    
>>> ['b', 'c', 'd', 'a']


    Well, as for the comments, you can use OrderedDict



    from collections import OrderedDict
    
s=['a', 'b', 'c', 'd', 'a']
    
print(list(OrderedDict.fromkeys(s)))





    share|improve this answer





















    • 1





      I imagine if you are not allowed to use another list you are not allowed to use a set, but even if you were, this would then become a clear duplicate.

      – juanpa.arrivillaga
      Nov 22 '18 at 17:13






    • 2





      This solution uses, even if implicitly, another list. :-)

      – Sidon
      Nov 22 '18 at 17:16


















    -1














    You can use set



    s=['a', 'b', 'c', 'd', 'a']
    
s=list(set(s))
    
print(s)
    
>>> ['b', 'c', 'd', 'a']


    Well, as for the comments, you can use OrderedDict



    from collections import OrderedDict
    
s=['a', 'b', 'c', 'd', 'a']
    
print(list(OrderedDict.fromkeys(s)))





    share|improve this answer





















    • 1





      I imagine if you are not allowed to use another list you are not allowed to use a set, but even if you were, this would then become a clear duplicate.

      – juanpa.arrivillaga
      Nov 22 '18 at 17:13






    • 2





      This solution uses, even if implicitly, another list. :-)

      – Sidon
      Nov 22 '18 at 17:16
















    -1












    -1








    -1







    You can use set



    s=['a', 'b', 'c', 'd', 'a']
    
s=list(set(s))
    
print(s)
    
>>> ['b', 'c', 'd', 'a']


    Well, as for the comments, you can use OrderedDict



    from collections import OrderedDict
    
s=['a', 'b', 'c', 'd', 'a']
    
print(list(OrderedDict.fromkeys(s)))





    share|improve this answer















    You can use set



    s=['a', 'b', 'c', 'd', 'a']
    
s=list(set(s))
    
print(s)
    
>>> ['b', 'c', 'd', 'a']


    Well, as for the comments, you can use OrderedDict



    from collections import OrderedDict
    
s=['a', 'b', 'c', 'd', 'a']
    
print(list(OrderedDict.fromkeys(s)))






    share|improve this answer














    share|improve this answer



    share|improve this answer








    edited Nov 22 '18 at 17:16

























    answered Nov 22 '18 at 17:12









    Sandesh34Sandesh34

    254112




    254112








    • 1





      I imagine if you are not allowed to use another list you are not allowed to use a set, but even if you were, this would then become a clear duplicate.

      – juanpa.arrivillaga
      Nov 22 '18 at 17:13






    • 2





      This solution uses, even if implicitly, another list. :-)

      – Sidon
      Nov 22 '18 at 17:16
















    • 1





      I imagine if you are not allowed to use another list you are not allowed to use a set, but even if you were, this would then become a clear duplicate.

      – juanpa.arrivillaga
      Nov 22 '18 at 17:13






    • 2





      This solution uses, even if implicitly, another list. :-)

      – Sidon
      Nov 22 '18 at 17:16










    1




    1





    I imagine if you are not allowed to use another list you are not allowed to use a set, but even if you were, this would then become a clear duplicate.

    – juanpa.arrivillaga
    Nov 22 '18 at 17:13





    I imagine if you are not allowed to use another list you are not allowed to use a set, but even if you were, this would then become a clear duplicate.

    – juanpa.arrivillaga
    Nov 22 '18 at 17:13




    2




    2





    This solution uses, even if implicitly, another list. :-)

    – Sidon
    Nov 22 '18 at 17:16







    This solution uses, even if implicitly, another list. :-)

    – Sidon
    Nov 22 '18 at 17:16















    -1














    You can cast the list to a set and the cast that back to a list.



    l = [1, 1, 2, 2, 3]
    
s = set(l)
    
list_without_duplicates = list(s)





    share|improve this answer




























      -1














      You can cast the list to a set and the cast that back to a list.



      l = [1, 1, 2, 2, 3]
      
s = set(l)
      
list_without_duplicates = list(s)





      share|improve this answer


























        -1












        -1








        -1







        You can cast the list to a set and the cast that back to a list.



        l = [1, 1, 2, 2, 3]
        
s = set(l)
        
list_without_duplicates = list(s)





        share|improve this answer













        You can cast the list to a set and the cast that back to a list.



        l = [1, 1, 2, 2, 3]
        
s = set(l)
        
list_without_duplicates = list(s)






        share|improve this answer












        share|improve this answer



        share|improve this answer










        answered Nov 22 '18 at 17:24









        Pablo PaglillaPablo Paglilla

        29715




        29715






























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