Reversing singly Linked list, METHOD 2, iterative

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 SinglyLinkedListNode* reverse(SinglyLinkedListNode* head) 

{
SinglyLinkedListNode*prev, *current, *next;
prev=0, next=0;
current=head;
while(current!=0)
{
    next=current->next;
    current->next=prev;
    prev=current;
    current=next;
}
head=prev;
return head;
}

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