What is the time complexity of adding an element to a Singly Linked List?

Question

Accepted Answer

Time complexity to add an element to a Singly Linked List is O(1) if added at the end using Tail pointer, and O(n) if added anywhere in the middle.

Adding an element at the end of a Singly Linked List using the Tail pointer is a constant time operation, hence O(1).
Adding an element anywhere in the middle of a Singly Linked List requires traversing the list to find the insertion point, resulting in a time complexity of O(n).
For example, if we have a Singly Linked List with 5 elements and we want to add a new element at the end, the time complexity would be O(1). However, if we want to add a new element in the middle of the list, the time complexity would be O(n) depending on the position of insertion.

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