Leetcode 217. Contains Duplicate. Python (Easiest Approach ✅)

217. Contains Duplicate

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.

Example 1:

Input: nums = [1,2,3,1]
Output: true

Example 2:

Input: nums = [1,2,3,4]
Output: false

Example 3:

Input: nums = [1,1,1,3,3,4,3,2,4,2]
Output: true

Constraints:

1 <= nums.length <= 105
-109 <= nums[i] <= 109

class Solution:
    def containsDuplicate(self, nums: List[int]) -> bool:
        hs = set() 
        for n in nums:
            if n in hs:
                return True
            hs.add(n)
            
        return False

Explaination :

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