Why are all lists getting same values - python?

Question

string_to_sort = 'Sorting1234'

l = list(string_to_sort)

uppers = numbers = lowers = list() # this is the trouble, but dont know why

for char in l:
    if char.isupper():
        print("it's upper: " + char)
        uppers.append(char)
    elif char.islower():
        print("it's lower " + char)
        lowers.append(char)
    elif char.isdigit():
        print("it's digit: " + char)
        numbers.append(char)

print(uppers)
print(lowers)
print(numbers)

the 3 lists all have same content, but when I init-d the lists , I just made them empty, not related to each other. What's the reason all 3 lists get same content?

`uppers = numbers = lowers = list()` creates a single list and three references to it. You are just modifing the same list — Valentino, May 14 '19 at 18:56

score 1 · Accepted Answer · answered May 14 '19 at 18:56

1

You are creating single list and refer it from three variables. If you want three separate lists, initialize them separately:

uppers = list()
numbers = list()
lowers = list()

answered May 14 '19 at 18:56

Marcin Orlowski

68,918
10
117
136

Why are all lists getting same values - python?

1 Answers1