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Remove Duplicates from a List

Certification: Basic Level Accuracy: 85.37% Submissions: 41 Points: 5

Write a Python program that removes all duplicate elements from a given list while preserving the original order.

Example 1
    

  • Input: list = [1, 2, 3, 1, 2, 5, 6, 7, 8, 6]
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  • Output: [1, 2, 3, 5, 6, 7, 8]
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  • Explanation: 
      

    • Step 1: Iterate through the original list, keeping track of elements seen so far.
      • 

    • Step 2: For each element, if it hasn't been seen before, add it to the result list.
      • 

    • Step 3: If the element has been seen before, skip it.
      • 

    • Step 4: Return the result list containing only the first occurrence of each element.
      • 

    •
Example 2
    

  • Input: list = [10, 20, 30, 40, 50]
    • 

  • Output: [10, 20, 30, 40, 50]
    • 

  • Explanation: 
      

    • Step 1: Iterate through the original list.
      • 

    • Step 2: Since all elements are unique, each element is added to the result list.
      • 

    • Step 3: The resulting list remains the same as the input list.
      • 

    •
Constraints
    

  • 1 ≤ list_length ≤ 10^6
    • 

  • -10^9 ≤ list[i] ≤ 10^9
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  • Time Complexity: O(n) where n is the length of the input list
    • 

  • Space Complexity: O(n) to store the unique elements
    •
SetListTech MahindraDropbox
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Hint
Solution

Solution Hints

    
        
  • Use a set to track seen elements
    • 
        
  • Iterate through the list once
    • 
        
  • Add elements to the result list only if not seen before
    •

Steps to solve by this approach:

 Step 1: Initialize an empty set to track seen elements.

 Step 2: Create an empty list to store the result with duplicates removed.

 Step 3: Iterate through each element in the input list.

 Step 4: Check if the element has been seen before.

 Step 5: If the element is not in the seen set, add it to both the set and result list.

 Step 6: Return the list with duplicates removed while preserving original order.

Submitted Code :