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Duplicate Elements in Array
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Duplicate Elements in Array

EasyPython

Problem

Write a simple program to find duplicate elements in an array using basic loops.

Implement find_duplicates(arr), which accepts a list of integers and returns each value that appears more than once, included only once in the output. Preserve the order in which duplicate values are first detected. The expected approach should use basic loops rather than a set or dictionary.

Constraints

  • 0 <= len(arr) <= 1000
  • -10^9 <= arr[i] <= 10^9
  • Return each duplicated value at most once
  • Preserve duplicate discovery order

Function Signature

def find_duplicates(arr):
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