C Linked List

Linked List

Linked list is very common data structure and often used to store similar data in memory.

Linked list are not stored in adjacent locations and array occupy continuous locations.

Linked list is a collection of elements called nodes, each of which stores two items of information - an element of the list and a link.

Link is a pointer or an address that indicates explicitly the location of the node containing the successor of the list element.

C Program To Implement Linked List and Operations

#include<stdio.h>  


//structure contains data and link
struct node
{
    int data;
    struct node *link;
};

// Adds the node at the linked list end
void append(struct node **head, int data)
{
    struct node *temp, *tail;
    temp = *head;

    // if linked list is empty, adding as first node.
    if(*head == NULL)
    {
        temp = malloc( sizeof (struct node));
        temp->data = data;
        temp->link = NULL;
        *head = temp;
    }
    // adding in the last if linked list is not empty
    else
    {
        //Move to last node
        while(temp->link != NULL)
        {
            temp = temp->link;
        }
        tail = malloc( sizeof (struct node));
        tail->data = data;
        tail->link = NULL;
        temp->link = tail;
    }
    
}

// Displays the linked list
void display(struct node *head)
{
    printf("\n");
    // traversing entire linked list
    printf("\nhead==>");
    while(head != NULL)
    {
        printf("%d-->", head->data);
        head = head->link;
    }
    printf("tail");
}

// returns the number of elements in the linked list.
int count(struct node *head)
{
    int c = 0;
    while(head != NULL)                                                         
    {                                                                           
        head = head->link;          
        c++;
    } 
    return c;
}

// delete the element in the linked list.
int delete(struct node **head, int data)
{
    struct node *old, *temp;
    temp = *head;

    while(temp != NULL)
    {
        if(temp->data == data)
        {
            // deleting first node if data matches
            if(temp == *head)
            {
                *head = temp->link;
                free(temp);
                return 1;
            }
            // deleting other nodes except first node
            else
            {
                old->link = temp->link;
                free(temp);
                return 1;
            }
        }
        // old points to the previous node
        old = temp;
        temp = temp->link;
    }
    return 0;
}

// Add element as the linked list first elements
void addfirst(struct node **head, int data)
{
    struct node *temp;

    // adding new node
    temp = malloc(sizeof(struct node));

    temp->data = data;
    temp->link = *head;
    *head = temp;
}

// Add the element at specified location.
int addafter(struct node *head, int location, int data)
{
    struct node *temp, *tail;
    int i=1;

    //temp = *head;
    //printf("%d", location);
    temp = head;
    // skip till desired location
    while(i<location-1)
    {
        temp = temp->link;
        i++;
        if(temp == NULL)
        {
            printf("There are less than %d elements in the linked list", location);
            return 0;
        }
    }
    // insert new node at desired location
    tail = malloc(sizeof(struct node));
    tail->data = data;
    tail->link = temp->link;
    temp->link = tail;
    return 1;
}




void main()                                                                     
{       
    int op, data, loc;                                                                        
    struct node *ptr;                                                           
    // Empty linked list                                                        
    ptr = NULL;                                                                 
                                                                                
    printf("\nNumber of elements in the linked list: %d", count(ptr));          
    append(&ptr, 1);                                                            
    append(&ptr, 2);                                                            
    append(&ptr, 3);                                                            
                                                                                
    display(ptr);       
    printf("\nNumber of elements in the linked list: %d", count(ptr));

    do
    {
        printf("\nLinked List\n---------------\n1.Add element in begining \n2.Add element in end\n3.Add element in specific location\n4.delete\n5.display\n6.count\n0.exit");
        printf("\nEnter choice: ");
        scanf("%d", &op);
        switch(op)
        {
            case 3:
                printf("\nEnter element: ");
                scanf("%d", &data);
                printf("\nEnter location: ");
                scanf("%d", &loc);
                addafter(ptr, loc, data);
                break;
            case 1:
                printf("\nEnter element: ");                                    
                scanf("%d", &data);                                             
                addfirst(&ptr, data);
                break;
            case 2:
                printf("\nEnter element: ");                                    
                scanf("%d", &data);                                             
                append(&ptr, data);  
                break;
            case 4:
                printf("\nEnter element: ");                                    
                scanf("%d", &data);                                             
                delete(&ptr, data);  
                break;
            case 5:
                display(ptr);
                break;
            case 6:
                printf("\nNumber of elements in the linked list: %d", count(ptr));
                break;
        }
    }while(op>=1 && op<=6);
}    
                                                                                                                                                                                                                                                                                                                                                                                                           
Compilation:
$ cc linked-list.c 
linked-list.c: In function ‘append’:
linked-list.c:18:16: warning: implicit declaration of function ‘malloc’ [-Wimplicit-function-declaration]
         temp = malloc( sizeof (struct node));
                ^~~~~~
linked-list.c:18:16: warning: incompatible implicit declaration of built-in function ‘malloc’
linked-list.c:18:16: note: include ‘’ or provide a declaration of ‘malloc’
linked-list.c:31:16: warning: incompatible implicit declaration of built-in function ‘malloc’
         tail = malloc( sizeof (struct node));
                ^~~~~~
linked-list.c:31:16: note: include ‘’ or provide a declaration of ‘malloc’
linked-list.c: In function ‘delete’:
linked-list.c:76:17: warning: implicit declaration of function ‘free’ [-Wimplicit-function-declaration]
                 free(temp);
                 ^~~~
linked-list.c:76:17: warning: incompatible implicit declaration of built-in function ‘free’
linked-list.c:76:17: note: include ‘’ or provide a declaration of ‘free’
linked-list.c:83:17: warning: incompatible implicit declaration of built-in function ‘free’
                 free(temp);
                 ^~~~
linked-list.c:83:17: note: include ‘’ or provide a declaration of ‘free’
linked-list.c: In function ‘addfirst’:
linked-list.c:100:12: warning: incompatible implicit declaration of built-in function ‘malloc’
     temp = malloc(sizeof(struct node));
            ^~~~~~
linked-list.c:100:12: note: include ‘’ or provide a declaration of ‘malloc’
linked-list.c: In function ‘addafter’:
linked-list.c:125:12: warning: incompatible implicit declaration of built-in function ‘malloc’
     tail = malloc(sizeof(struct node));
            ^~~~~~
linked-list.c:125:12: note: include ‘’ or provide a declaration of ‘malloc’
Output:
$ ./a.out 

Number of elements in the linked list: 0

head==>1-->2-->3-->tail
Number of elements in the linked list: 3
Linked List
---------------
1.Add element in begining 
2.Add element in end
3.Add element in specific location
4.delete
5.display
6.count
0.exit
Enter choice: 1

Enter element: 23

Linked List
---------------
1.Add element in begining 
2.Add element in end
3.Add element in specific location
4.delete
5.display
6.count
0.exit
Enter choice: 5


head==>23-->1-->2-->3-->tail
Linked List
---------------
1.Add element in begining 
2.Add element in end
3.Add element in specific location
4.delete
5.display
6.count
0.exit
Enter choice: 6

Number of elements in the linked list: 4
Linked List
---------------
1.Add element in begining 
2.Add element in end
3.Add element in specific location
4.delete
5.display
6.count
0.exit
Enter choice: 2

Enter element: 45

Linked List
---------------
1.Add element in begining 
2.Add element in end
3.Add element in specific location
4.delete
5.display
6.count
0.exit
Enter choice: 5


head==>23-->1-->2-->3-->45-->tail
Linked List
---------------
1.Add element in begining 
2.Add element in end
3.Add element in specific location
4.delete
5.display
6.count
0.exit
Enter choice: 6

Number of elements in the linked list: 5
Linked List
---------------
1.Add element in begining 
2.Add element in end
3.Add element in specific location
4.delete
5.display
6.count
0.exit
Enter choice: 4

Enter element: 2

Linked List
---------------
1.Add element in begining 
2.Add element in end
3.Add element in specific location
4.delete
5.display
6.count
0.exit
Enter choice: 5


head==>23-->1-->3-->45-->tail
Linked List
---------------
1.Add element in begining 
2.Add element in end
3.Add element in specific location
4.delete
5.display
6.count
0.exit
Enter choice: 6

Number of elements in the linked list: 4
Linked List
---------------
1.Add element in begining 
2.Add element in end
3.Add element in specific location
4.delete
5.display
6.count
0.exit
Enter choice: 0

$ ./a.out 

Number of elements in the linked list: 0

head==>1-->2-->3-->tail
Number of elements in the linked list: 3
Linked List
---------------
1.Add element in begining 
2.Add element in end
3.Add element in specific location
4.delete
5.display
6.count
0.exit
Enter choice: 3

Enter element: 45

Enter location: 2

Linked List
---------------
1.Add element in begining 
2.Add element in end
3.Add element in specific location
4.delete
5.display
6.count
0.exit
Enter choice: 5


head==>1-->45-->2-->3-->tail


C Program Examples

C program to cmpute matrix addition using two dimensional array

C program to cmpute matrix subtraction using two dimensional array

C program to cmpute matrix multiplication using two dimensional array

C program to compute different order of matrix multiplication

C program to generate identity matrix for required rows and columns

C program to validate whether matrix is identity matrix or not

C program to validate whether matrix is sparse matrix or not

C program to validate whether matrix is dense matrix or not

C program to generate string as matrix diagonal characters using two dimesional array

C Program to find number of weeks, months and years from days

C Program To Implement Linked List and Operations

C Program To Implement Sorted Linked List and Operations

C Program to Reverse the Linked List

C Program to Stack and Operations using Linked List

C Program to Queue and Operations using Linked List

C Program to calculate multiplication of two numbers using pointers

C Program To Calculate Median

C Program To Calculate Standard Deviation

C Program For Fahrenheit To Celsius Conversion

C Program To Calculate Average

C Program For Quadratic Equations

C Program To Check Character Type

C Program To Find Largest Of Three Values

C Program To Find Max Value In Array

C Program to Find Min Value In Array

C Program to Print Multiplication Table

C Program for Frequency Counting

C Program to read a line of text

C Program To Find ASCII Value For Any Character

C Program To Find A Character Is Number, Alphabet, Operator, or Special Character

C Program To Find Reverse Case For Any Alphhabet using ctype functions

C Program To Find Number Of Vowels In Input String

C Program Pointers Example Code

C Program To Find Leap Year Or Not

C Program To Swap Two Integers Using Call By Reference

C Program To Swap Two Integers Without Using Third Variable

C Program To List Prime Numbers Upto Limit

C Program To List Composite Numbers Upto Limit

C Program To Calculate Compound Interest

C Program To Calculate Depreciation Amount After of Before Few Years

C Program To Calculate Profit Percentage

C Program To Calculate Loss Percentage

C Program To Find String Is Polindrome Or Not

C Program To Find Factorial of a Number

C Program To Check Number is a Polindrome or Not

C Program To Generate Random Integers

C Program To Generate Random Float Numbers

C Program to find Square Root of a Number

C Program to find Area of a Rectangle

C Program to find Perimeter of a Rectangle

C Program to find Area of a Square

C Program to find Area of a Triangle

C Program to find Area of a Parallelogram

C Program to find Area of a Rhombus

C Program to find Area of a Trapezium

C Program to find Area of a Circle and Semi-circle

C Program to find Circumference of a Circle and Semi-circle

C Program to find length of an arc

C Program to find Area of a Sector

C Program to find string length for list of strings

C Program to find the character at index in a string

C Program to compare characters

C Program to find eligible to vote or not

C Program to get system current date and time on linux

C Program to get positive number

C Program to implement calculator

C Program to implement banking system

C Program to find sum of number

C Program for array traversal using pointers

C Program for array traversal in reverse order using pointers

C Program to find particular element occurrences count in array

C Program to find even elements occurrences count in array

C Program to find odd elements occurrences count in array

C program to find week day in word from week day in number using two dimentsional array

C program to find month in word from month in number using pointers

C program to compute PMT for a loan

C program to compute EMI and round up using floor

C program to compute EMI and round up using ceil

C program to compute the EMI table with Interest, Principal and Balance

C program to get multiple line of string

C program to find nth element in array using pointers

C program to compute the volume of a cube

C program to compute the volume of a box

C program to compute the volume of a sphere

C program to compute the volume of a triangular prism

C program to compute the volume of a cylinder

C Program to Compute Perimeter of Square

C Program to compute the perimeter of triangle

C Program to compute the discount rate

C Program to compute the sales tax

C program to add, delete, search a record or show all using binary file

C program to add, delete, search a record or show all using text file

Privacy Policy  |  Copyright@2017 - All Rights Reserved.  |  Contact us   |  Report website issues in Github   |  Facebook page   |  Google+ page

Email Facebook Google LinkedIn Twitter
^