This code is optimized and will produce result faster than with the one chosen as the best answer.This code saves from going into a very long process of chasing the forward and backward node pointer which will occur in the following case if we follow the 'best answer' method.Look through the dry run of the following and you will realize what I am trying to say.Then look at the problem through the given method below and measure the no. of steps taken to find the answer.
1->2->9->3 ^--------^
Here is the code:
boolean loop(node *head)
{
node *back=head;
node *front=head;
while(front && front->next)
{
front=front->next->next;
if(back==front)
return true;
else
back=back->next;
}
return false
}