int main()
{
for (size_t i: {0, 1, 2, 4, 5, 9, 10}) {
std::cout << "Test case i = " << i << ":" << std::endl;
auto root = create(i);
print(root);
root = pairwise_swap(root);
print(root);
destroy(root);
std::cout << std::endl;
}
return 0;
}
void main() {
struct listnode *head = NULL;
add(&head, getnode(1));
add(&head, getnode(2));
add(&head, getnode(3));
add(&head, getnode(4));
add(&head, getnode(5));
add(&head, getnode(6));
print_list(head);
reverse(&head);
print_list(head);
head = pairwise_swap(head);
print_list(head);
head = pairwise_swap(head);
print_list(head);
rotate(&head, 3);
print_list(head);
segregate_even_odd(&head);
print_list(head);
int a = add_digit(head, 9);
print_list(head);
}
struct listnode * pairwise_swap(struct listnode *head) {
// never forget to add error cases
if(head == NULL || head->next == NULL) {
return head;
}
struct listnode *newhead;
struct listnode *remaining;
newhead = head->next;
remaining = head->next->next;
newhead->next = head;
head->next = pairwise_swap(remaining);
return newhead;
}
int main (int argc, char *argv[])
{
char ch;
int choice;
int ret_val = 0;
struct node *head = NULL;
int *data = NULL;
int value = 0;
int pos = -1;
while (1) {
printf("\nMENU\n\n");
printf("1. Insert at the front\n");
printf("2. Insert at a position\n");
printf("3. Delete from the front\n");
printf("4. Delete from a position\n");
printf("5. Display\n");
printf("6. Reverse the linked list\n");
printf("7. Pairwise Swap\n");
printf("\nEnter your choice\n");
scanf("%d", &choice);
switch (choice)
{
case 1:
printf("\nEnter a value\n");
scanf(" %d", &value);
data = get_new_node(&value);
ret_val = insert_node(&head, (void *)data);
if (ret_val)
printf("\nOperation failed\n");
break;
case 2:
printf("\nEnter the position at which to insert\n");
scanf(" %d", &pos);
printf("\nEnter a value\n");
scanf(" %d", &value);
data = get_new_node(&value);
ret_val = insert_node_pos(&head, pos, (void *)data);
if (ret_val)
printf("\nOperation failed\n");
break;
case 3:
ret_val = delete_node(&head);
if (ret_val)
printf("\nOperation failed\n");
break;
case 4:
printf("\nEnter the position at which to delete\n");
scanf(" %d", &pos);
ret_val = delete_node_pos(&head, pos);
if (ret_val)
printf("\nOperation failed\n");
break;
case 5:
print_list(head);
break;
case 6:
head = reverse(head);
break;
case 7:
pairwise_swap(&head);
break;
default:
printf("\nWrong choice. Doing nothing\n");
}
printf("Do you want to continue (y/n) ??");
scanf(" %c", &ch);
if (ch == 'n' || ch == 'N') {
printf("\nBreaking the driver loop\n");
break;
}
}
return 0;
}
