Operations_on_Linked_List

#include<stdio.h>
#include<stdlib.h>
struct node
{
    int data;
    struct node *next;
}*head;
void print()
{
    struct node *temp;
    temp=head;
    if(temp!=NULL)
    {
        printf("The List is :\n");
        while(temp!=NULL)
        {
            printf("%d->",temp->data);
            temp=temp->next;
        }
    }
    printf("\n");
}
void insert_at_start(int data)
{
    struct node *new_node;
    new_node=(struct node *)malloc(sizeof(struct node));
    new_node->data=data;
    new_node->next=head;
    head=new_node;
}
void insert_at_end(int data)
{
    struct node *temp,*new_node;
    temp=head;
    new_node=(struct node *)malloc(sizeof(struct node));
    new_node->data=data;
    if(temp==NULL)
        insert_at_start(data);
    else
    {
    while(temp->next!=NULL)
    {
        temp=temp->next;
    }
    temp->next=new_node;
    new_node->next=NULL;
    }
}
void insert_at_middle(int data,int position)
{
    int i;
    struct node *temp,*new_node;
    new_node=(struct node*)malloc(sizeof(struct node));
    new_node->data=data;
    temp=head;
    for(i=1;i<position-1;i++)
        temp=temp->next;
    new_node->next=temp->next;
    temp->next=new_node;
}
void delete_from_start()
{
    struct node *temp;
    temp=head;
    if(temp==NULL)
       printf("The list is empty.\n");
    else
    {
        head=temp->next;
        free(temp);
    }
}
void delete_from_end()
{
    struct node *temp,*var;
    temp=head;
    while(temp->next!=NULL)
    {
        var=temp;
        temp=temp->next;
    }
    free(temp);
    var->next=NULL;
}
int delete_from_middle(int position)
{
    int i;
    struct node *temp,*temp2;
    temp=head;
    for(i=1;i<(position-1);i++)
    {
        temp=temp->next;
    }
    temp2=temp->next;
    temp->next=temp2->next;
    temp2->next=NULL;
    free(temp2);
}
int main()
{
    head=NULL;
    int i,val,loc;
    printf("1.Insertion at the beginning.\n");
    printf("2.Insertion at the end.\n");
    printf("3.Insert at any position.\n");
    printf("4.Delete from beginning.\n");
    printf("5.Delete from end.\n");
    printf("6.Delete from middle.\n");
    printf("7.Exit.\n");
    while(1)
    {
        printf("Enter Your Choice : ");
        scanf("%d",&i);
        switch(i)
        {
        case 1:
            {
                printf("Enter the value of the node : ");
                scanf("%d",&val);
                insert_at_start(val);
                print();
                break;
            }
        case 2:
            {
                printf("Enter the value of the node : ");
                scanf("%d",&val);
                insert_at_end(val);
                print();
                break;
            }
        case 3:
            {
                printf("Enter the value and position of the node : ");
                scanf("%d%d",&val,&loc);
                insert_at_middle(val,loc);
                print();
                break;
            }
        case 4:
            {
                delete_from_start();
                print();
                break;
            }
        case 5:
            {
                delete_from_end();
                print();
                break;
            }
        case 6:
            {
                printf("Enter the node to be deleted : ");
                scanf("%d",&loc);
                delete_from_middle(loc);
                print();
                break;
            }
        case 7:
            exit (0);
        }
    }
    return 0;
}