Print unsorted dictionary in Python

Question

I want to print out the unsorted dictionary, but it came out sorted.

This is the code I use (Version 2.7.5 Linux):

# id and name array are not the actual input. It is just a sample input. (So no hard-coding please) 
# More importantly, I just want to figure out how to have the unsorted dictionary.

id = [1 ,4, 2] 
name = ["John" , "Mary", "Alice"]
my_dict = {}

for x in range(len(id)):
    my_dict[id[x]] = name[x]

for key, val in my_dict.items():
    print(key, val)

Expected Output:

(1, "John")
(4, "Mary")
(2, "Alice")

Actual Output:

(1, "John")
(2, "Alice")
(4, "Mary")

dictionary in python is never sorted. what you are seeing is just something that happened by chance. https://stackoverflow.com/questions/327311/how-are-pythons-built-in-dictionaries-implemented — Mox, Aug 23 '19 at 06:55
then when i do key_list = list(my_dict.keys()). i expect to see key_list as [1 , 4 , 2 ] but it returned me with [1, 2 , 4]. — Jojoleo, Aug 23 '19 at 07:07
pls refer to the link that i have shared. it depends on hashing — Mox, Aug 23 '19 at 07:17

score 1 · Answer 1 · answered Aug 23 '19 at 06:54

It is not sorted. In Python 2.7 (and pre-3.7 releases) dictionaries are unordered; meaning them they can be stored in any order. In your test, by coincidence, they are stored in such a way. If you try the same test using Python 3.7 you will see your expected result.

If you want to keep the creation order on Python 2.7, use an OrderedDict instead.

Print unsorted dictionary in Python

1 Answers1