Python checking for duplicates in a list

Question

Hey guys I dont want the console to print duplicated letters can anyone solve this?

import random

random_list = ["a","b","c","d","e","f"]

for i in range(5):
    test = random.choices(random_list)
    print(test)

Use `random.sample` (sample without replacement) with `k=5` and then iterate over the resultant choice set (or just print the entire thing, whatever). — wkl, Aug 22 '22 at 00:54
Welcome to Stack Overflow. Please read the [documentation](https://docs.python.org/3/library/random.html) for the `random` standard library module. In particular, notice that it tells you that `random.choices` will give results "with replacement", meaning that it is allowed to repeat the values. (Of course, this code asks it for *one* value at a time, in a loop, which defeats the purpose anyway.) To get the values without replacement, you want `random.sample` instead. — Karl Knechtel, Aug 22 '22 at 07:10
In the future, [please try](https://meta.stackoverflow.com/questions/261592/) to [look up answers yourself](https://duckduckgo.com/?q=site%3Astackoverflow.com+python+choose+without+duplicates) before posting. — Karl Knechtel, Aug 22 '22 at 07:11

score -1 · Answer 1 · answered Aug 22 '22 at 01:03

-1

remove the item after you print it with .pop()

import random

random_list = ["a","b","c","d","e","f"]

for i in range(5):
    test = random.choices(random_list)[0]
    random_list.pop(random_list.index(test))
    print(test)

answered Aug 22 '22 at 01:03

Chris B

24
3

score -1 · Answer 2 · answered Aug 22 '22 at 07:02

You have different options.

simply remove the item from the existing list.
create a used list and check that items are not in that list.

here is an example of method 2:

import random

random_list = ["a","b","c","d","e","f"]
used_list = []

for i in range(5):
    test = random.choices(random_list)
    if test not in used_list:
        print(test)
    used_list.append(test)

Python checking for duplicates in a list

2 Answers2