fhslacrosse13

i have a problem with a free function. It is suppost to merge two lists together but when i run it it does something weird that i cant figure out

also, i have some code commented out and replaced so just look over that.
[HTML]#include <iostream>
#include "d_nodel.h"

using namespace std;

//free function merge
void merge(dnode<int> *list1, dnode<int> *list2);

int main(){
int arrA[] = {1,2,6,9,12,23,33,45,55,68,88,95};
int arrB[] = {2,8,12,25,33,48,55,75,105};
dnode<int> *list1 = new dnode<int>;
dnode<int> *list2 = new dnode<int>;
for (int i = 0; i < 12; i++)
insert(list1, arrA[i]);
for (int j = 0; j < 9; j++)
insert(list2, arrB[j]);
writeDLinkedList(list1);
cout<<endl;
writeDLinkedList(list2);
cout<<endl;
merge(list1, list2);
writeDLinkedList(list1);
return 0;
}

//implement merge
void merge(dnode<int> *list1, dnode<int> *list2){
dnode<int> *plist1 = list1->next, *plist2 = list2->next, *p;
while (plist1 != list1 && plist2 != list2){
if (plist1->nodeValue < plist2->nodeValue)
plist1 = plist1->next;
else {
/*p = plist2->next;
plist2->prev = plist1->next;
plist2->next = plist1->prev;
plist2 = p;*/
p = plist2;
plist2 = plist2->next;
p->prev->next = p->next;
p->prev = plist1->prev->next;
p->next = plist1;
plist1->prev->next = p;
plist1->prev = p;
}
}
if (plist1 != list1);
else{
while (plist2 != list2){
/*p = plist2->next;
plist2->prev = plist1->next;
plist2->next = plist1->prev;
plist2 = p;*/
p = plist2;
plist2 = plist2->next;
p->prev->next = p->next;
p->prev = plist1->prev->next;
p->next = plist1;
plist1->prev->next = p;
plist1->prev = p;
}
}
}[/HTML]

fhslacrosse13

i dont think i was descriptive enough with what merge does. It takes to two lists and comparing them and making them one list. when merge finishes list2 should be empty and list1 should be: {1,2,6,8,9,12,23,25,33,45,48,55,68,75,88,95,105}

The Dark

In this code
I think the red highlighted code should be since you are trying to insert the node between plist1->prev and plist1.
Also, in the blue highlighted code, you are setting the p->prev->next to p->next to fix the forward link, but you also need to fix up p->next->prev to point to p->prev to fix up the backward link.

Both of these would only be stuffing up the reverse links, which may not be causing your problem.

Can you post the .h file so I can try it out through a debugger?

Also
means nothing to me - you need to say what it is doing.