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Interview: Remove Loop in linked list - Java

I was asked this question in interview: "How to detect the loop in linked list?", I solved this but immediately the interviewer asked me how do I remove the loop in a linked list. I fumbled.

So any pointers on how to solve this, may be pseudo code, or method definition?

I'm comfortable with Java so I have tagged this question under java.

For Instance this linked list has a loop

 0--->1---->2---->3---->4---->5---->6
 ▲さんかく |
 | ▼
 11<—-22<—-12<—-9<—-8

Answer*

*Easiest and unique way*
------------------------

To solve this problem we just count no of nodes (**that's it**). **I bet you haven't seen this solution till now in any competitive website, because i made it today on my own...**

 void removeTheLoop(Node *root)
 {
 std :: unordered_set < struct Node * > s;
 if(root == NULL)
 return ;

 s.insert(root);
 int before_size = s.size();

 while(1)
 {
 if(root -> next == NULL)
 return;
 s.insert(root -> next);
 if(before_size == s.size())
 {
 root -> next = NULL;
 return;
 }
 before_size = s.size();
 root = root -> next;
 }
 }


**How it works:** 

**TIME COMPLEXITY: O(n)...SPACE COMPLEXITY: O(n)**

 - It simply counts the no of elements. We will take unordered_set in c++. 
 - It inserts the element if it is not present in the container and increases its size. 
 - Now the suspense begins when the node comes that point to the node that already added , so in that case size doesn't increase and we will make next to that as NULL. 

**UPVOTE IT IF YOU THINK IT IS UNIQUE.**
----------------------------------------

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Interview: Remove Loop in linked list - Java

Answer*