2.8 Reverse a Linked List - Iterative Method | Data Structure Tutorials

In this lecture I have written C program to reverse a singly linked list. I have followed iterative approach to solve this problem.

******************************************
See Complete Playlists:

*********************************************

Connect & Contact Me:

#linkedlistindatastructure
#algorithms
#dsa
#operationsonlinkedlist

[somhua]

This has to be the best linkedlist reversal video on the internet. Mam, you’re so good at breaking down such confusing logic into something so simple. You’re really blessed to be a teacher

[himanshumangal]

Finally someone who is teaching assuming the viewers are beginners.

[riadhaidar]

because of you ma'am i've understood everything in singly linked list and here is the full code :
#include <stdio.h>
#include <stdlib.h>
struct node {
int data;
struct node *next;
}*head, *newnode, *temp;
int pos;
int n;
void create(int n);
void print();
void addbig();
void addend();
void addspecific(int pos);
void delbeg();
void delend();
void delspecpos();
void getlength();
void reverse();
int main()
{
int num, choice;
while(1){
printf("\nENTER '1' TO CREATE LINKED LIST: \n");
printf("\nENTER '2' TO ADD NODE AT BEGINNING: \n");
printf("\nENTER '3' TO ADD AT NODE THE END OF THE LIST: \n");
printf("\nENTER '4' TO ADD NODE AT SPECIFIC POSITION: \n");
printf("\nENTER '5' TO DELETE THE FIRST NODE: \n");
printf("\nENTER '6' TO DELETE LAST NODE: \n");
printf("\nENTER '7' TO DELETE A NODE FROM SPECIFIC POSITION: \n");
printf("\nENTER '8' TO GET LENGTH OF THE LIST: \n");
printf("\nENTER '9' TO REVERSE THE LIST: \n");
printf("\nENTER '10' TO EXIT: \n");
scanf("%d", &num);
switch (num)
{
case 1:
create(n);
print();
break;
case 2:
addbig();
print();
break;
case 3:
addend();
print();
break;
case 4:
addspecific(pos);
print();
break;
case 5:
delbeg();
print();
break;
case 6:
delend();
print();
break;
case 7:
delspecpos();
print();
break;
case 8:
getlength();
print();
break;
case 9:
reverse();
print();
break;
case 10:
printf("bye bye :) !!");
exit(0);
break;
default:
printf("WRONG CHOICE...!");
}//end of switch statement
}//end of while
return 0;
}//end of main
void create(int n)
{
printf("enter the length of the list: ");
scanf("%d", &n);
struct node *newnode;
head=0;
int i;
for(i=0;i<n;i++)
{
newnode=(struct node*)malloc(sizeof(struct node));
printf("enter the data of node: ");
scanf("%d", &newnode->data);
newnode->next=0;
if (head==0)
{
head=temp=newnode;
}
else {temp->next=newnode;
temp=newnode;
}
}
}
void print()
{
temp=head;
printf("\nthe list is: \n");
while(temp!=0)
{
printf("%d ", temp->data);
temp=temp->next;
}

}
void addbig()
{
struct node *newnode;
if (head==0)
{
printf("invalid position");
}
else
{
newnode=(struct node *)malloc(sizeof(struct node));
printf("\nenter the data of new beginning node: ");
scanf("%d", &newnode->data);
newnode->next=head;
head=newnode;
}
}
void addend()
{
struct node *newnode;
temp=head;
if(head==0)
{
printf("invalied position");
}
else{
newnode=(struct node*)malloc(sizeof(struct node));
printf("\nenter the data of new last node: ");
scanf("%d", &newnode->data);
newnode->next=0;
while(temp->next!=0)
{
temp=temp->next;
}
temp->next=newnode;
}
}
void addspecific(int pos)
{
int j;
printf("\nenter position of newnode: ");
scanf("%d", &pos);
struct node *newnode;
if (pos>n||pos<0)
{
printf("invalid position");
}
else{
temp=head;
newnode=(struct node*)malloc(sizeof(struct node));
printf("\nenter the data of newnode: ");
scanf("%d", &newnode->data);
for(j=0;j<pos-2;j++)
{
temp=temp->next;
}
newnode->next=temp->next;
temp->next=newnode;
}
}
void delbeg()
{
printf("\n first node will be deleted....\n");
if (head==0)
{
printf("lsit is empty");
}
else
{

temp=head;
head=head->next;
free(temp);
}

}
void delend()
{

struct node *prevnode;
printf("\nlast node will be deleted....\n");
temp=head;
while(temp->next!=0)
{
prevnode=temp;
temp=temp->next;
}
if(temp==head)
{head=0;
}
else{
prevnode->next=0;
}
free (temp);

}
void delspecpos()
{
int x;
int posi;
struct node *nextnode;
temp=head;
printf("\nenter the position of node you want to delete: ");
scanf("%d", &posi);
for(x=0;x<posi-2;x++)
{
temp=temp->next;
}
nextnode=temp->next;
temp->next=nextnode->next;
free(nextnode);
}
void getlength()
{
temp=head;
int count;
while(temp!=0)
{
count++;
temp=temp->next;
}
printf("\n list length is: %d", count);
}
void reverse()
{
struct node *prevnode, *current, *nextnode;
prevnode=0;
current=nextnode=head;
while(nextnode!=0)
{
nextnode=nextnode->next;
current->next=prevnode;
prevnode=current;
current=nextnode;
}
head=prevnode;
}

[anubharathor]

Teachers like you are needed seriously....who give not only theories and codes....but knowledge also....

[sreeharimysore]

Reversing the linked list is always a confusing stuff for me. But finally I got this concept clear with your unique style of explanation. Very grateful to you MadamJi ... !

[AYAMDASH]

Finally a video for all
levels of students.Its deeply intriguing and really helps boulangerie of epic proportions

[somsuryananda]

Dear Jenny,
You seem to enlighten us on a daily basis. Your way of teaching is very simple and yet very impacting. Thank you for all you have done/posted. 😊😊 Wish you all success in life and career.

[pratikpatil]

This is my favorite u tube channel to learn data structure and algoritham... thanks mam💻

[sachinkainth]

I have 20 years of development experience in industry but still I have found reversing a linked list to be quite difficult, until that is I came across this excellent video.

[pragmaticcoder]

No background music, No fancy introduction of channel or anything. Simple, to the point and perfect explanation. Thank you and God bless you.

[bhadreesh]

Hi Ma'am Happy Teachers Day....Ma'am Your Teaching is so Understandable that any Below Average Students can also easily Grasp the Concepts..Jayanti Ma'am please Cover all the Concepts of "Advanced Data Structures & Algorithms" without leaving even a Single Concept...You are also having so "Beautiful Face along with Beautiful Voice & Genius Brain"💐🎂...You will Definitely become one of the Reputed Youtube Professor in front of the Whole World...I will be waiting for that Day👍

[SanjayKIG]

Finally someone who is teaching assuming the viewers are beginners. Subscribing the channel for more viewership and exposure. Good luck. We really dont mind the long length of the videos.

[mridupawan]

YOU'RE TRUELY ONE OF THE FINEST TEACHERS!!

[anupamanand]

Whenever i watch your video it feels like i was sitting in the classroom. I spent my whole one day but not find out how to reverse. finally after watching this video i solve the problem in minutes.

[yuktagaba]

Thanks a lot for making us understand this easily. I went through a lot of videos but yours is actually the "BEST" one.

[saqibjaved]

Just one word for u mam "ZABARDAST" .
GREAT explanation and simple style, and i loved my all teachers but u r one of the best teacher ever on dsa.😍😍😍😍

[aritralahiri]

Most simple and clear explanation I've come across so far . Keep us providing with more of these wonderful videos. Much appreciated !

[MDSHAHABUDDIN-eprc]

Blessed, thrilled, excited all at the same time to have a teacher like you!!

[aashishshrestha]

feel like tuition class.. thank you madam .. from Nepal

[gabriellerosa]

PERFEITA MARAVILHOSA SEM DEFEITOS, toda vez que tenho que reverter uma lista eu colo aqui <3