Can you explain the main differences between array, dictionary, and set in the context of programming?

The main differences between array, dictionary, and set:

• Array — an ordered collection of elements, accessed by index. Allows duplicates and preserves order.

• Dictionary (or Map) — a collection of key-value pairs, where each key is unique and maps to a value. Accessed by key.

• Set — an unordered collection of unique elements, without duplicates. Used for fast lookup and existence checks.

Example in Python:

arr = [1, 2, 2, 3]  # Array with duplicates

dict = {'a': 1, 'b': 2}  # Dictionary with keys 'a' and 'b'

set_ = {1, 2, 3}  # Set of unique elements
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