Find Common Elements
Practice Python set operations to efficiently handle unique elements and perform mathematical set operations. You will work with multiple collections to find intersections, unions, and differences using Python built-in set data structure.
Your goal is to leverage set operations to solve problems involving uniqueness and membership testing. Sets provide O(1) average-case lookup time, making them ideal for these operations.
Example 1:
Input: list1 = [1, 2, 3, 4], list2 = [3, 4, 5, 6]
Output: [3, 4]
Explanation: Find common elements (intersection).
Example 2:
Input: items = [1, 2, 2, 3, 3, 3, 4]
Output: [1, 2, 3, 4]
Explanation: Get unique elements only.
Example 3:
Input: list1 = [1, 2, 3], list2 = [2, 3, 4]
Output: [1]
Explanation: Find elements only in list1 (difference).
Algorithm Flow

Best Answers
def find_common(list1, list2):
s1 = set(list1)
s2 = set(list2)
return list(s1 & s2)Comments (0)
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