Reverse Singly linked list, METHOD 1, RECURSIVE (head globally declared)

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void rev(struct node* temp)
{
    if(temp->next==0)
    {head=temp;
    return;}
    rev(temp->next);
    tempnext=temp->next;
    tempnext->next=temp;
    temp->next=0;
    
}
int main()
{
    ....
    ....
    //head is passed as parameter from main.
    rev(head);
    ....
    ...
}

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