Contains Duplicate
Detailed guide and Python implementation for the 'Contains Duplicate' problem.
Problem Statement
Given an integer array nums, return True if any value appears at least twice in the array, and return False if every element is distinct.
Write a function containsDuplicate(nums: List[int]) -> bool.
- •1 <= len(nums) <= 10^5
- •-10^9 <= nums[i] <= 10^9
Examples
nums = [1, 2, 3, 1]
True
The element 1 appears at index 0 and index 3, so there is a duplicate.
nums = [1, 2, 3, 4]
False
All elements are distinct.
nums = [1, 1, 1, 3, 3, 4, 3, 2, 4, 2]
True
Multiple elements repeat: 1, 3, 4, and 2.
Need a Hint?
Edge Cases to Watch
- Empty input structures
- Single element inputs
- Large numerical bounds
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