Tag: counter

Anagrams are strings that have the same letters but in a different order for example abc, bca, cab, acb, bac are all anagrams, since they all contain the same letters.

We can check whether two strings are anagrams in Python in different ways. One way to do that would be to use Counter from the collections module.

From the documentation:

 A Counter is a dict subclass for counting hashable objects. It is a collection where elements are stored as dictionary keys and their counts are stored as dictionary values. Counts are allowed to be any integer value including zero or negative counts. The Counter class is similar to bags or multisets in other languages.

In plain English, with Counter, we can get a dictionary that represents the frequency of elements in a list. Let us see this in an example:

 from collections import Counter
 ​
 print(Counter("Hello"))  # Counter({'l': 2, 'H': 1, 'e': 1, 'o': 1})

Now we can use Counter to quickly check whether two strings are anagrams or not:

 from collections import Counter
 ​
 ​
 def check_if_anagram(first_string, second_string):
     first_string = first_string.lower()
     second_string = second_string.lower()
     return Counter(first_string) == Counter(second_string)
 ​
 ​
 print(check_if_anagram('testinG', 'Testing'))  # True
 print(check_if_anagram('Here', 'Rehe'))  # True
 print(check_if_anagram('Know', 'Now'))  # False

We can also check whether 2 strings are anagrams using sorted():

 def check_if_anagram(first_word, second_word):
     first_word = first_word.lower()
     second_word = second_word.lower()
     return sorted(first_word) == sorted(second_word)
 ​
 print(check_if_anagram("testinG", "Testing"))  # True
 print(check_if_anagram("Here", "Rehe"))  # True
 print(check_if_anagram("Know", "Now"))  # False

That’s basically it.

I hope you find this useful.