14. Contains Duplicate#217
Easy📊 Arrays & HashingHash Set
Return true if any value appears at least twice in the array.
Examples
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]]
Output: true
Why learn this
The simplest hash set problem — just check for repeats. First step into set-based thinking.
ArraysHash Sets
Python 3Loading Python engine...
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