Reverse a Linked List Code/Algorithm/Program

Given a Singly Linked List. Reverse the Linked list.

[abhishekrajanofficial]

Superb explanation Sir.
Here's another approach of reversing a linkedlist recursively-
private static LinkedListNode start, LinkedListNode prev) {
if (start == null || start.next == null) {
start.next = prev;
return start;
}
LinkedListNode second = start.next;
start.next = prev;
return reverseLinkedList(second, start);
}

[aadeshn]

Amazing, worth watching, thank you sir, khup madat Parat ekda Banvat rha videos...

[sarthaksrivastav]

Your visualization thing is very helpful. Thank you.

[wizardfire]

Sir interview me web project ke liye kis type ke project se kaam chl sakta h or jada problem na ho.
1. Complete mern stack project.
2. Any simple react project
3. Simple With html, css or javascript.
4. Any dsa project
5. Or any dbms.

Inme se konse rakha acha rhega or sirf kitno se kaam ho jayega pls reply.

[abinvarkey]

but if we return q after breaking at if(q==NULL) then how we can get head of reversed list?

[holyshit]

We can simplify his code a little bit if we assume that we have lazy boolean evaluation
node *reverse(node *head)
{
node *p, *q;
if(head == NULL || head->next == NULL)
return head;
p = head;
q = p->next;
q = reverse(q);
p->next->next = p;
p->next = NULL;
return q;
}

[priyankamorankar]

From this code it seems, "p->next->next = p" is getting executed only once. But it should be executed number of times recursive function is executed. Could you please explain this?

[aakashgoswami]

hats off to you sir..you deserve million subscribers.

[miasevda]

Please Sir can we change this instruction :
P->next->next =p
By
q->next = p

[dr.padmajapulicherla]

Sir....all your videos are so good...you write code first on board and explain in a beautiful way....thank you...Dr.Padmaja.Pulicherla

[sauru]

Can you please make solution video for Divide Two Integers. Thank you.

[holyshit]

It is time to iterative approach now
Solution based on stack

node * reverse(node *head)
{
node *p, *q, *r;
p = NULL; // we intialize pointer to reversed list
q = head; // we initialize traversal pointer
while(q != NULL)
{
r = q->next // we save next pointer in list with original order of elements
q->next = p;
p = q; // In these two lines we perform push operation known from stack
q = r; // we get pointer to the next element
}
return p;
}

[mihirsheth]

sir u have described the function which returns a node, then how can u simply write return without mentioning any pointer along with it.At last how will we able to know the address of new head??

[yogifarm]

need to use a tail variable for deleting the last node from a link list :( please help

[hajarchaibi]

is this algorithm valid in c langage ???

[NeverGiveUp_oo]

This code will not give correct output in computer. For correction We need to return head Pointer from base case then it will work.

[ashokbhandari]

could you please make one or two videos regarding working of recursions, i.e. like generating binary strings for given no.s etc

[beleynewwubagegn]

I don't understand efficiently please sir how i identify the head and null or execute

[vivekhattarge]

May I know, Why have you stopped posting videos?

[manasranjan]

Thanks a lot. Really you have the teaching capability. Any one can understand.