void mergeSort(struct node **head_ref)
{
struct node *head = *head_ref;
if(head == NULL || head->next == NULL) return;
struct node *a=NULL;
struct node *b=NULL;
frontBackSplit(head,&a,&b);
mergeSort(&a);
mergeSort(&b);
*head_ref = sortedMerge(a,b);
}
//merge sort for linked list
void mergeSort(Node **headRef) {
Node *head = *headRef;
Node *a;
Node *b;
if((head ==NULL)||(head->next==NULL)) {
return;
}
frontBackSplit (head, &a, &b); // split head into a, b sublists
mergeSort(&a);
mergeSort(&b);
*headRef = sortedMerge(a,b); // merge to sorted list
}
void RecordList::mergeSort(RecordListNode **headRef) {
RecordListNode *head = *headRef;
RecordListNode *a;
RecordListNode *b;
/* Base case -- length 0 or 1 */
if ((head == NULL) || (head->_next == NULL)) {
return;
}
/* Split head into 'a' and 'b' sublists */
frontBackSplit(head, &a, &b);
/* Recursively sort the sublists */
mergeSort(&a);
mergeSort(&b);
/* answer = merge the two sorted lists together */
*headRef = sortedMerge(a, b);
}
int main(){
int c, n, r;
do {
printf("0. Show\n");
printf("1. Append\n");
printf("2. Push\n");
printf("3. pop\n");
printf("4. Count Nodes\n");
printf("5. Get nth element\n");
printf("6. Delete List\n");
printf("7. Insert at nth index\n");
printf("8. InsertSort the List\n");
printf("9. FrontBackSplit\n");
printf("10. Remove Duplicates\n");
printf("11. Reverse the List\n");
printf("12. Alternating Split\n");
printf("13. Make a Dummy List\n");
printf("14. Shuffle Merge\n");
printf("15. EXIT\n");
printf("Your Choice : ");
scanf("%d", &c);
switch(c){
case 0 : show();
break;
case 1 : printf("Enter a number : ");
scanf("%d", &n);
append(n);
break;
case 2 : printf("Enter a number : ");
scanf("%d", &n);
push(n);
break;
case 3 : if((r = pop()) > 0)
printf("%d\n", r);
else
printf("List Empty\n");
break;
case 4 : printf("%d\n", countNodes());
break;
case 5 : printf("Enter the index : ");
scanf("%d", &n);
((r = getNth(n)) >= 0) ? printf("%d\n", r) : printf("Index out of Range\n");
break;
case 6 : deleteList();
break;
case 7 : printf("Enter the index and the number : ");
scanf("%d%d", &r, &n);
if(insertNth(r, n) < 0)
printf("Index out of Range. Aborting...");
break;
case 8 : insertSort();
break;
case 9 : frontBackSplit();
break;
case 10: removeDuplicate();
break;
case 11: reverse();
break;
case 12: alternatingSplit();
break;
case 13: makeDummyList();
break;
case 14: shuffleMerge();
break;
case 15: exit(0);
default: printf("wrong Choice\n");
exit(0);
}
}while(c >= 0 && c <= 14);
}
