How to reset a linked list i reversed

I have a reverse method that messes with the original linked list inputted; however usually this is fixable by just reversing.

my problem is after i reverse it, how do i recover the original linked list?

Code:

---

//compares p and q; if p is smaller, then return -1; if q is smaller, return 1
//return 0 if its exactly the same
int compare(struct integer* p, struct integer* q) {
  int count=1, count2=1;
  struct integer *ptest=p, *qtest=q;
  while(ptest->next!=NULL) {
      ptest=ptest->next;
      count++;           
  }
  printf("count p= %d\n",count);
  while(qtest->next!=NULL) {
      qtest=qtest->next;
      count2++;           
  }
  //PTEST AND QTEST ARE CURRENTLY POINTING TO LAST DIGIT OF P AND Q
  printf("count q= %d\n",count2);
  if(count<count2) {
      printf("p is less than q; returning -1\n");
      return -1;
  }
  else if(count>count2) {
      printf("q is less than p; returning 1\n");
      return 1; 
  }
  else {
      printf("p=%d and q are equal length; no return yet\n",ptest->digit);
      if(ptest->digit<qtest->digit) {
        printf("returning -1\n");
        return -1;             
      }
      else if(ptest->digit>qtest->digit) {
        printf("returning 1\n");
        return 1; 
      }
      else {
       
      }
      return 0;
  }
}
}

//---------------PART OF ANOTHER FUNCTION; SEGMENT

      p=reverse(p);
      q=reverse(q);
      printf("\nRevp: ");
      print(p);
      printf("-Revq: ");
      print(q);
      printf("\n");
      while(p!=NULL && q!=NULL) {
        if(p->digit<q->digit) {
            printf("first else\n");
            p=reverse(p);
            q=reverse(q);
            free(ptest);
            free(qtest);
            return -1;         
        }
        else if(p->digit>q->digit) {
            printf("second else\n");
            p=reverse(p);
            q=reverse(q);
            free(qtest);
            free(ptest);
            return 1;
        }
      p=p->next;
      q=q->next;
      }
      return 0;

---

Well if your reverse function works properly, reverse it again.

ohh! maybe i should explain better;

i do reverse it again, however, due to the p=p->next; and q=q->next at end of while to compare, i lose the ones at the front of the number, makes sense???

the problem is i tried a struct integer* p=altp and substituted all the stuff to altp so i'd save the address of the first number, but it doesnt work =/ same output

Then your reverse function doesn't work. If it did, you would simply call it over again:

Code:

---

type *list;
...
rev( &list ); /* or... */
list = rev( list );
...
/* later on... */
...
rev( &list ); /* or... */
list = rev( list );

---

So, what's your reverse function look like, and how are you calling it?


Quzah.

my reverse function is up top...and it works just fine...just messes up the pointers up so it cant reclaim the previous order; i usually do just recall it twice; but the problem is i cant because the pointers move during the while loop, and when i have holder pointers, it screws up

my problem is that after i run these two methods, the number

6347 becomes 347 =[ i made a current pointer

struct integer* current=p; then did all my stuff with p, and then made p=current;, but its cut off, dishambled, many different kind of errors, hep lz?