sll

//SLL
#include<stdio.h>
#include<conio.h>
#include<stdlib.h>
//struct of node
struct sll
{
    int info;
    struct sll *next;
}*start=NULL,*temp=NULL,*prev=NULL,*node=NULL,*next1=NULL;
//create node
void create_node()
{
    int val;
    node=(struct sll *)malloc(sizeof(struct sll));
    if(node==NULL)
    {
        printf("\n Memory not allocated");
        return;
    }

    printf("\nEnter the Value: ");
    scanf("%d",&val);
    node->info=val;
    node->next=NULL;

}
//display the sll
void disp()
{
    if(start==NULL)
    {
        printf("\n The S.L.L. is empty");

    }
    else
    {
        temp=start;
        while(temp!=NULL)
        {
            printf("\n\t %d",temp->info);
            temp=temp->next;
        }
    }
}
//Insert from begining

void insert_beg()
{
    create_node();
    if(start==NULL)
    {
        start=node;

    }
    else
    {
        node->next=start;
        start=node;
    }
    disp();

}
//Insert from End

void insert_end()
{

    if(start==NULL)
    {
        insert_beg();

    }
    else
    {
        temp=start;
        while(temp->next!=NULL)
        {
            temp=temp->next;
        }
        create_node();
        temp->next=node;
        disp();
    }


}
// insert after specific value;
void insert_after_val()
{
    int val,flag=0;
    if(start==NULL)
    {
        printf("\n Empty S.L.L. For Values");
    }
    else
    {
        printf("Enter the specific value from sll: ");
        scanf("%d",&val);
        temp=start;
        while(temp->next!=NULL)
        {
            if(temp->info==val)
            {
                create_node();
                node->next=temp->next;
                temp->next=node;
                flag=1;
                break;
            }
            temp=temp->next;

        }
        if(flag==0)
        {
            printf("\n[ Value does not FOUND ]");
        }
        else
        {
            disp();
        }
    }
}
//insert via position
void insert_after_posi()
{
    int val,flag=0,i=0;
    if(start==NULL)
    {
        printf("\n[ Empty S.L.L. for position ]");
    }
    else
    {
        printf("Enter the specific position from sll: ");
        scanf("%d",&val);
        temp=start;
        while(temp!=NULL)
        {
            i++;
            if(i==val)
            {
                create_node();
                node->next=temp->next;
                temp->next=node;
                flag=1;
                break;
            }
            temp=temp->next;
        }
        if(flag==0)
        {
            printf("\n[Position is invalid]");
        }
        else
        {
            disp();
        }

    }

}
//delete from begining
void del_beg()
{
    int data;
    if(start==NULL)
    {
        printf("\n[ No value for Delete ]");
    }
    else
    {
        temp=start;

        start=temp->next;
        free(temp);
    }
    disp();
}
//delete from End
void del_end()
{
    int data;
    if(start==NULL)
    {
        printf("\n[ No value for Delete ]");
        return;
    }
    temp=start;
    if(temp->next==NULL)
    {
        del_beg();
        return;
    }
    else
    {

        while(temp->next!=NULL)
        {
            prev=temp;
            temp=temp->next;
        }

        prev->next=NULL;
        free(temp);
    }
    disp();
}
//delete at specific value;
void del_at_val()
{
    int data,flag=0,val;
    if(start==NULL)
    {
        printf("\n[ No value for Delete ]");
        return;
    }
        else
    {
        printf("\n Enter the Value from Sll: ");
        scanf("%d",&val);
        temp=start;
        if(start->info==val)
        {
            del_beg();
            return;
        }

        while(temp!=NULL)
        {


            if((temp->info)==val)
            {
                flag=1;
                prev->next=temp->next;
                free(temp);
                break;

            }
            prev=temp;
            temp=temp->next;
        }
        if(flag==0)
        {
            printf("\n [ Invalid Value for delete ]");
        }
        else
        {
            disp();
        }

    }

}
//delete at specific position;
void del_at_pos()
{
    int data,flag=0,val,i=0;
    if(start==NULL)
    {
        printf("\n[ No value for Delete ]");
        return;
    }
    else
    {

        printf("\n Enter the position from Sll: ");
        scanf("%d",&val);

        temp=start;
        if(start->info==val)
        {
            del_beg();
            return;
        }

        while(temp!=NULL)
        {
            i++;
            if(1==val)
            {
                del_beg();
                return;
             }
            if(i==val)
            {
                flag=1;
                prev->next=temp->next;
                free(temp);
                break;

            }
            prev=temp;
            temp=temp->next;
        }
        if(flag==0)
        {
            printf("\n [ Invalid Value for delete ]");
        }
        else
        {
            disp();
        }

    }

}

// main functions;
int main()
{
    int ch;
    do
    {
        printf("\n\t===>\tMenu\t<===");
        printf("\n\t1.Insert from begining");
        printf("\n\t2.Insert at the end");
        printf("\n\t3.Insert after specific value");
        printf("\n\t4.Insert after specific position");
        printf("\n\t5.delete from begining");
        printf("\n\t6.delete from End");
        printf("\n\t7.delete specific value");
        printf("\n\t8.Insert after specific position");
        printf("\n\t9.Display");
        printf("\n\t10 EXIT");
        printf("\n\n Enter your choice: ");
        scanf("%d",&ch);
        switch(ch)
        {
            case 1:
                insert_beg();
                break;
            case 2:
                insert_end();
                break;
            case 3:
                insert_after_val();
                break;
            case 4:
                insert_after_posi();
                break;

            case 5:
                del_beg();
                break;
            case 6:
                del_end();
                break;
            case 7:
                del_at_val();
                break;
            case 8:
                del_at_pos();
                break;

            case 9:
                disp();
                break;
            default:
                printf("\n (*_*)²");

                break;

        }
    }while(ch>=1 && ch<10);


    return 0;
}