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Python BasicsEasy
Finding Non Repeating elements in an Array
Learn how to solve the 'Finding Non Repeating elements in an Array' problem. This detailed resource details brute force and optimized approaches.
Problem Statement
Easy
Write a function find_non_repeating(arr) that takes a list of integers arr and returns a sorted list of all elements that appear exactly once in the array. If no such element exists, return an empty list.
Constraints
- •0 <= len(arr) <= 10^5
- •-10^6 <= arr[i] <= 10^6
Examples
Example 1
Input
arr = [1, 2, 3, 2, 4, 3]
Output
[1, 4]
Explanation
1 appears once and 4 appears once. 2 and 3 each appear twice.
Example 2
Input
arr = [5, 5, 5]
Output
[]
Explanation
5 appears 3 times. No element appears exactly once.
Example 3
Input
arr = [7, 8, 9]
Output
[7, 8, 9]
Explanation
All elements appear exactly once.
Need a Hint?
Use simple arithmetic operators (like modulo `%`, division `//`), conditional checks, or loops to inspect number properties.
Edge Cases to Watch
- Empty list or null input variables
- Single item lists/arrays
- Extremely large input bounds causing integer or stack overflow
Ready to Solve?
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