Problem Solving: Write code to remove duplicates from an unsorted linked list.

By Tapos Pal 

Problem

Write code to remove duplicates from an unsorted linked list.



Solution

Two types of solution came to my mind
1) Use hashmap to check the duplicates and remove that as necessary. Time complexity for this solution is O(n) and Space Complexity O(n)
2) We also can check if by checking all previous entries for duplciate. In this case time complexity will  be O(n^2) and Space Complexity O(1)



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