public static void Start()
{
Noder start = new Noder(1);
start.next = new Noder(2);
start.next.next = new Noder(3);
start.next.next.next = new Noder(4);
start.next.next.next.next = new Noder(5);
// 1's random points to 3
start.random = start.next.next;
// 2's random points to 1
start.next.random = start;
// 3's and 4's random points to 5
start.next.next.random = start.next.next.next.next;
start.next.next.next.random = start.next.next.next.next;
// 5's random points to 2
start.next.next.next.next.random = start.next;
Console.WriteLine("Original List");
PrintList(start);
Console.WriteLine("Cloned List");
Noder x = CloneUsingHashMap(start);
PrintList(x);
}
static void PrintList(Noder start)
{
Noder ptr = start;
while (ptr != null)
{
Console.WriteLine("Data = " + ptr.data + ", Random = " + ptr.random.data);
ptr = ptr.next;
}
}
// This function clones a given
// linked list in O(1) space
private static Noder CloneInConstantSpace(Noder start)
{
Noder curr = start,
temp = null;
// insert additional node after every node of original list
while (curr != null)
{
temp = curr.next;
// Inserting node
curr.next = new Noder(curr.data);
curr.next.next = temp;
curr = temp;
}
curr = start;
// adjust the random pointers of the newly added nodes
while (curr != null)
{
if (curr.next != null)
{
curr.next.random = (curr.random != null)? curr.random.next : curr.random;
}
// move to the next newly added node by skipping an original node
curr = (curr.next != null) ? curr.next.next : curr.next;
}
Noder original = start, copy = start.next;
// save the start of copied linked list
temp = copy;
// now separate the original list and copied list
while (original != null && copy != null)
{
original.next = (original.next != null) ? original.next.next : original.next;
copy.next = (copy.next != null) ? copy.next.next : copy.next;
original = original.next;
copy = copy.next;
}
return(temp);
}
//Time Complexity O(n)
//Space Complexity O(n)
private static Noder CloneUsingHashMap(Noder head)
{
if (head == null)
{
return(null);
}
Dictionary <Noder, Noder> Map = new Dictionary <Noder, Noder>(); //map will store all nodes as key and new nodes as value
Noder clone;
Noder orginal = head;
//iterate and insert new nodes in map
while (orginal != null)
{
clone = new Noder(orginal.data);
Map.Add(orginal, clone); //key = original node , value = new Node(original node data)
orginal = orginal.next;
}
orginal = head; //bring the pointer to head again
while (orginal != null)
{
clone = Map[orginal];
if (orginal.next != null)
{
clone.next = Map[orginal.next];
}
if (orginal.random != null)
{
clone.random = Map[orginal.random];
}
orginal = orginal.next;
}
//all the values in map are now pointing to correct next and random address.
//return head of cloned node..
return(Map[head]); //this will return corrosponding cloned head
}
public Noder(int d)
{
data = d;
next = null;
}
