#Linked List

Reverse a linked list in pairs. For example, given the input 1 → 2 → 3 → 4 → 5, the output should be 2 → 1 → 4 → 3 → 5.

Implement an algorithm to detect a loop in a linked list. Consider edge cases in your approach.

Given a linked list with a cycle, write a method to find and return the node at which the cycle begins. Discuss the logic behind your approach, including any flowchart or diagram if necessary.

Write a function to determine if a linked list has a cycle in it. If there is a cycle, return the node where the cycle begins. Discuss the approach and the time complexity of your solution.

Given a linked list, remove the Nth node from the end of the list. The solution should maintain a linear time complexity and constant space complexity. Provide the implementation details and discuss edge cases.