## Microsoft Interview Question

Software Engineer / DevelopersMaintain a pointer to the tail of one linked list. When you need to merge, just use the tail pointer to access the last node of the list and point it's next pointer to the 2nd linked list. Maintaining the tail pointer to the last node of one list is O(1). Merging is also O(1). If maintaining the pointer to the last node of one list is not allowed then the algorithm requires atleast O(n) where 'n' is the length of the smaller of the two linked lists.

Maintain a pointer to the tail of one linked list. When you need to merge, just use the tail pointer to access the last node of the list and point it's next pointer to the 2nd linked list. Maintaining the tail pointer to the last node of one list is O(1). Merging is also O(1). If maintaining the pointer to the last node of one list is not allowed then the algorithm requires atleast O(n) where 'n' is the length of the smaller of the two linked lists.

```
public void MergeList(SingleLinkedList l1, SingleLinkedList l2)
{
if(l1.Head == null)
l1.Head=l2.Head;
if(l2.Head==null)
return;
ListNode index1=l1.Head, index2=l2.Head;
if(index2.Value < l1.Head.Value)
{
l2.Head = l2.Head.Next;
index2.Next=l1.Head;
l1.Head = index2;
index1 = l1.Head;
index2 = l2.Head;
}
while(index1.Next!=null && index2!=null)
{
if(index2.Value > index1.Value && index2.Value<=index1.Next.Value)
{
temp = index2;
index2=index2.Next;
temp.Next = index1.Next;
index1.Next = temp;
}
index1= index1.Next;
}
if(index1.Next==null)
index1.Next = index2;
}
```

```
node * merge (node * l1, node * l2)
{
node Head={0};
node *t = &Head;
while (l1 && l2)
{
if (l1->v > l2->v)
{ t->next = l2; l2 = l2->next; }
else
{ t->next = l1; l1 = l1->next; }
t = t->next;
}
if (l1)
t->next = l1;
else
t->next = l2;
return Head.next;
}
```

MS IDC makes fool of people.

People have to come to office on weekends due to workload and do night outs, no work life balance. They pay 10-20% more make people labour.

Do take the feedback from employees before joining MS.

And work is junk, all junk wor from Redmond is transferred to IDC. Ask any team, whether they design, implement products or just do porting or maintenance or make tools.

```
node *merge(node *a, node *b)
{
node *tmp, *head;
if (a == NULL)
return b;
else if (b == NULL)
return a;
/* saving the head pointer */
if (a->data < b->data)
{
tmp = a;
a = a->next;
}
else
{
tmp = b;
b = b->next;
}
head = tmp;
/* looping */
while(1)
{
if (a == NULL)
{
tmp->next = b;
break;
}
else if (b== NULL)
{
tmp->next = a;
break;
}
else if (a->data < b->data)
{
tmp->next = a;
tmp = tmp->next;
a = a->next;
}
else if (a->data > b->data)
{
tmp->next = b;
tmp = tmp->next;
b = b->next;
}
}
return head;
}
```

- gulusworld1989 October 16, 2010