Counting Distinct Elements in an Array
Detailed guide and Python implementation for the 'Counting Distinct Elements in an Array' problem.
Problem Statement
Write a function count_distinct(arr) that takes a list of integers arr and returns the count of distinct (unique) elements in the array.
- •0 <= len(arr) <= 10^5
- •-10^6 <= arr[i] <= 10^6
Examples
arr = [1, 2, 2, 3, 3, 3]
3
The distinct elements are 1, 2, and 3. Count = 3.
arr = [5, 5, 5, 5]
1
Only one distinct element: 5.
arr = [1, 2, 3, 4, 5]
5
All elements are distinct.
Need a Hint?
Edge Cases to Watch
- Empty input structures
- Single element inputs
- Large numerical bounds
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