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Reversing singly linked list?

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Join Date: Sep 2008

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Reversing singly linked list?

Sep 9th, 2008

could someone please show me how i would be able to reverse the printout of a linked list?, i have gotten it to print out in the right order but not sure how to make to printout in reverse.

here is my current code,

 Help with Code Tags 
 C++ Syntax (Toggle Plain Text) 
void print(node*& head)
{
	node* temp;
 
	temp = head;
 
	while (temp != NULL)
	{
		cout << temp->base;
		temp = temp->next;
	}
}
void print(node*& head)
{
	node* temp;

	temp = head;

	while (temp != NULL)
	{
		cout << temp->base;
		temp = temp->next;
	}
}

at the moment the print function prints out whats in the linked list in the correct order, i want it to do it in reverse, please help

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Join Date: Oct 2006

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niek_e

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Cenosillicaphobiac

Re: Reversing singly linked list?

Sep 9th, 2008

Your nodes don't have a link 'previous' (singly-linked), so as far as I can see, you'll have to store all the data in some sort of container (a vector for example, or another linked list

) and print that out in reverse order.

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Join Date: Aug 2008

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miepmuts

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Re: Reversing singly linked list?

Sep 9th, 2008

To reverse the printout of the linked list you can try something like the following:

 Help with Code Tags 
 C++ Syntax (Toggle Plain Text) 
void print(node*& head)
{
    node * temp = head;
    if (temp->next != null)
    {
        print(temp->next);
    }
 
    cout << temp->base; 
}
void print(node*& head)
{
    node * temp = head;
    if (temp->next != null)
    {
        print(temp->next);
    }

    cout << temp->base; 
}

This way you first recursively go to the last element of the linked list, and then start printing from back to the first element.

This is just theoretical though. I don't know (and don't have the tools present) if it will work in practice.