CODE EXAMPLE FOR C

Linked List using C

#include<stdio.h>
#include<stdlib.h>
void insertAtBeginning(int);
void insertAtEnd(int);
void insertBetween(int,int,int);
void display();
void removeBeginning();
void removeEnd();
void removenode(int);
struct Node
{
   int data;
   struct Node *next;
}*head = NULL;
int main()
{
   int opt,value,opt1,val1,val2;
 while(1)
 {
   mainmenu : printf("

 MENU 
1. Insert
2. Display
3. Delete
4. Exit
Enter your choice: ");
   scanf("%d",&opt);
   switch(opt)
   {
      case 1:   printf("Enter the value to be insert: ");
                scanf("%d",&value);
        while(1)
        {
                printf("Where you want to insert: 
1. At Beginning
2. At End
3. Between
Enter your choice: ");
                scanf("%d",&opt1);
                switch(opt1)
                {
                   case 1: insertAtBeginning(value);
                                   break; 
                   case 2: insertAtEnd(value);
                                   break;
                   case 3: printf("Enter the two values where you want to insert: ");
                                   scanf("%d%d",&val1,&val2);
                                   insertBetween(value,val1,val2);
                                break;
                                
                  /* default:   printf("
Wrong InputTry again");*/
                }
        goto mainmenu;
        }
        break;
                
      case 2:   display();
                break;
      case 3:   printf("How do you want to Delete: 
1. From Beginning
2. From End
3. given_node
Enter your choice: ");
                scanf("%d",&opt1);
                switch(opt1)
                {
                   case 1:      removeBeginning();
                                break;
                   case 2:      removeEnd(value);
                                break;
                   case 3:      printf("Enter the value which you want to delete: ");
                                scanf("%d",&val2);
                                removenode(val2);
                                break;
                   default:     printf("
Wrong Input!! Try again!!!

");
                                goto mainmenu;
                }
                break;
      case 4:   exit(0);
      default: printf("
Wrong input!!! Try again!!

");
   }
   }
}

void insertAtBeginning(int value)
{
   struct Node *newNode;
   newNode = (struct Node*)malloc(sizeof(struct Node));
   newNode->data = value;
   if(head == NULL)
   {
      newNode->next = NULL;
      head = newNode;
   }
   else
   {
      newNode->next = head;
      head = newNode;
   }
   printf("
One node inserted!!!
");
}
void insertAtEnd(int value)
{
   struct Node *newNode;
   newNode = (struct Node*)malloc(sizeof(struct Node));
   newNode->data = value;
   newNode->next = NULL;
   if(head == NULL)
        head = newNode;
   else
   {
      struct Node *temp = head;
      while(temp->next != NULL)
        temp = temp->next;
      temp->next = newNode;
   }
   printf("
One node inserted!!!
");
}
void insertBetween(int value, int loc1, int loc2)
{
   struct Node *newNode;
   newNode = (struct Node*)malloc(sizeof(struct Node));
   newNode->data = value;
   if(head == NULL)
   {
      newNode->next = NULL;
      head = newNode;
   }
   else
   {
      struct Node *temp = head;
      while(temp->data != loc1 && temp->data != loc2)
        temp = temp->next;
      newNode->next = temp->next;
      temp->next = newNode;
   }
   printf("
One node inserted!!!
");
}

void removeBeginning()
{
   if(head == NULL)
        printf("

List is Empty!!!");
   else
   {
      struct Node *temp = head;
      if(head->next == NULL)
      {
         head = NULL;
         free(temp);
      }
      else
      {
        head = temp->next;
        free(temp);
        printf("
One node deleted!!!

");
      }
   }
}
void removeEnd()
{
   if(head == NULL)
   {
      printf("
List is Empty!!!
");
   }
   else
   {
      struct Node *temp1 = head,*temp2;
      if(head->next == NULL)
        head = NULL;
      else
      {
         while(temp1->next != NULL)
         {
            temp2 = temp1;
            temp1 = temp1->next;
         }
         temp2->next = NULL;
      }
      free(temp1);
      printf("
One node deleted!!!

");
   }
}
void removenode(int delValue)
{
   struct Node *temp1 = head, *temp2;
   while(temp1->data != delValue)
   {
     if(temp1 -> next == NULL){
        printf("
Given node not found in the list!!!");
     }
     temp2 = temp1;
     temp1 = temp1 -> next;
   }
   temp2 -> next = temp1 -> next;
   free(temp1);
   printf("
One node deleted!!!

");
 }
void display()
{
   if(head == NULL)
   {
      printf("
List is Empty
");
   }
   else
   {
      struct Node *temp = head;
      printf("

List elements are - 
");
      while(temp->next != NULL)
      {
         printf("%d --->",temp->data);
         temp = temp->next;
      }
      printf("%d --->NULL",temp->data);
   }
}