What is the difference between Counter and Dictionary in Python?

What is the difference between Counter and Dictionary in Python?

In Python, a Dictionary is a built-in data type that stores key-value pairs, while Counter is a subclass of Dictionary from the collections module specifically designed to count hashable objects.

Can you give me an example of how to use Counter?

Sure! You can use Counter to count the occurrences of elements in a list. For example: from collections import Counter; counts = Counter(['a', 'b', 'a', 'c', 'b', 'a']); print(counts) will output Counter({'a': 3, 'b': 2, 'c': 1}).

Are there any performance differences between them?

Yes, Counters are optimized for counting and can be more efficient for that purpose, while Dictionaries are more general-purpose and may have overhead for counting tasks.

When should I use a Counter instead of a Dictionary?

Use a Counter when you need to count occurrences of items, as it provides convenient methods for that. Use a Dictionary for general key-value storage.