Challenge 5: Find Duplicates in Array

Write a function to find the duplicates in an array in the most efficient way!

Problem Statement

Given an array, find all the duplicates that exist in that array.


An array and its size


A vector with the duplicates if they exist, and an empty vector if they don’t.

Sample Input

  int arr[] = {1, 3, 4, 3, 5, 4, 100, 100};
  int arrSize = 8;

Sample Output

vector<int> output = {3, 4, 100};

Coding Exercise

Take a close look and design a step-by-step algorithm before jumping on to implementation. This problem is designed for your practice, so try to solve it on your own first. If you get stuck, you can always refer to the hint and solution provided in the code tab. Good Luck!

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