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Remove Duplicates from an Array

Certification: Basic Level Accuracy: 55.56% Submissions: 9 Points: 10

Write a C++ function to remove duplicates from an array of integers and return the new array.

Example 1
    

  • Input: arr = [1, 2, 2, 3, 4, 4]
    • 

  • Output: [1, 2, 3, 4]
    • 

  • Explanation: 
      

    • Step 1: Create an empty result array and a hash set to track seen elements.
      • 

    • Step 2: Iterate through the input array: [1, 2, 2, 3, 4, 4].
      • 

    • Step 3: For each element, check if it's already in the hash set.
      • 

    • Step 4: If not in the set, add it to both the set and the result array.
      • 

    • Step 5: Return the result array containing unique elements: [1, 2, 3, 4].
      • 

    •
Example 2
    

  • Input: arr = [5, 5, 5, 5]
    • 

  • Output: [5]
    • 

  • Explanation: 
      

    • Step 1: Create an empty result array and a hash set to track seen elements.
      • 

    • Step 2: Iterate through the input array: [5, 5, 5, 5].
      • 

    • Step 3: For each element, check if it's already in the hash set.
      • 

    • Step 4: If not in the set, add it to both the set and the result array.
      • 

    • Step 5: Return the result array containing unique elements: [5].
      • 

    •
Constraints
    

  • 1 ≤ array length ≤ 10^4
    • 

  • -10^5 ≤ array elements ≤ 10^5
    • 

  • Time Complexity: O(n)
    • 

  • Space Complexity: O(n)
    •
ArraysSetIBMSnowflake
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Hint
Solution

Solution Hints

    
  
  • Use a hash set to store unique elements.
    • 
  
  • Traverse the array and add elements to the set if they are not already present.
    • 
  
  • Convert the set back to an array and return it.
    •

Steps to solve by this approach:

 Step 1: Create a data structure (unordered_set) to track seen elements.

 Step 2: Create a vector to store the result (array without duplicates).

 Step 3: Iterate through each element of the input array.

 Step 4: For each element, check if it exists in our set of seen elements.

 Step 5: If not seen before, add it to both the result vector and the set of seen elements.

Submitted Code :