217. Contains Duplicate

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https://leetcode.com/problems/contains-duplicate/solution/

Given an array of integers, find if the array contains any duplicates.
Your function should return true if any value appears at least twice in the array, and it should return false if every element is distinct.
Example 1:
Input: [1,2,3,1]
Output: true
Example 2:
Input: [1,2,3,4]
Output: false
Example 3:
Input: [1,1,1,3,3,4,3,2,4,2]
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Intuition
Two approaches
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Sort the array, and check for consecutive duplicates
Time - O(N log N)
Space - O(1)
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Track elements in a set, and check for duplicates
Time - O(N)
Space - O(N)
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Related problems
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