Please check the code and mark the error

#1
#2

Hello, @anmolaggarwal.432,

Change your fast pointer initializtion:

ListNode* fast = head->next;

#3

Ya I got right it just want to know that i submitted mid point on leetcode with fast = head->next it showed error testcase did not get passed PLease resolve this

#4

@anmolaggarwal.432,

Let’s consider a simple linked list [ 3 -> 2 -> NULL ].

When fast = head, in the first iteration,
Your code will return midpoint as a node pointing to 2,
A will be pointing to 3 while B will be pointing to NULL,
So, A = 3 -> 2 -> NULL and B = NULL

Now, when A = Sortlist(A) is called, we would go back to the same position as in the first iteration ultimately leading to an infinite loop and the error.

Moreover,
For the given List midpoint should be 3 instead of 2.

#5

@anmolaggarwal.432,
Is it clear now?

#6

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