Program for Singly linked list

#include <stdio.h>

#include <stdlib.h>

struct node 

{

    int info;

    struct node *link;

};

struct node *first;

int main()

{

    struct node *ptr,*cpt,*tpt;

    int s;

    char n;

do

{

    printf("\nHi guys plase select the option to initiate the link list");

    printf("\nPress 1 for creation");

    printf("\nPress 2 for display");

    printf("\nPress 3 for insertion at the beginning");

    printf("\nPress 4 for insertion at end");

    printf("\nPress 5 for insertion at a given location");

    printf("\nPress 6 to delete from the beginning");

    printf("\nPress 7 to delete from the end");

    printf("\nPress 8 to delete a specific element");

    printf("\nPress 9 to terminate");

    printf("\nEnter your choice:");

    scanf("%d",&s);

    

    switch(s)

{

        case 1:

       

            //Create a new link list

    ptr=(struct node *)malloc(sizeof(struct node));

    printf("ENTER THE VALUE");

    scanf("%d",&ptr->info);

    first=ptr;

    

    do

    {

        cpt=(struct node *)malloc(sizeof(struct node));

    printf("ENTER THE VALUE");

    scanf("%d",&cpt->info);

    ptr->link=cpt;

    ptr=cpt;

    

    printf("\nEnter Y for more nodes");

    scanf("%s",&n);

    }

    while(n=='y');

    ptr->link=NULL;

     break;

      

    

    

     case 2: // Display a linked list

     

        ptr=(struct node *)malloc(sizeof(struct node));

    ptr=first;

    while(ptr!=0)

    {

        printf("%d\t",ptr->info);

        ptr=ptr->link;

    }

    break;

     

    case 3: tpt=(struct node *)malloc(sizeof(struct node));

    printf("ENTER THE VALUE");

    scanf("%d",&tpt->info);

    tpt->link=first;

    first=tpt;

    break;

    

    case 4:tpt=(struct node *)malloc(sizeof(struct node));

    printf("ENTER THE VALUE");

    scanf("%d",&tpt->info); 

    ptr=first;

    while(ptr->link!=NULL)

    {

        ptr=ptr->link;

    }

    ptr->link=tpt;

    tpt->link=NULL;

    break;

    

    case 5:   //Insert at a given location

 

        ptr=(struct node *)malloc(sizeof(struct node));

    int data;

    struct node *tpt;

    tpt=(struct node *)malloc(sizeof(struct node));

    printf("ENTER THE VALUE");

    scanf("%d",&tpt->info);

    printf("Enter the location in which insertion has to be made!");

    scanf("%d",&data);

    

    ptr=first;

    while(ptr->info!=data)

    {

        ptr=ptr->link;

    }

    tpt->link=ptr->link;

    ptr->link=tpt;

     ptr=(struct node *)malloc(sizeof(struct node));

    ptr=first;

    while(ptr!=0)

    {

        printf("%d\t",ptr->info);

        ptr=ptr->link;

    }

    break;

    case 6: ptr=first;

    first=ptr->link;

    free(ptr);

    break;

    

    case 7: ptr=first;

    while(ptr->link!=NULL)

    {

        cpt=ptr;

        ptr=ptr->link;

    }

    cpt->link=NULL;

    free(ptr);

    break;

    

    case 8:

        // Deletion of a specific location

        ptr=(struct node *)malloc(sizeof(struct node));

        cpt=(struct node *)malloc(sizeof(struct node));

    int loc;

     ptr=(struct node *)malloc(sizeof(struct node));

    ptr=first;

    while(ptr!=0)

    {

        printf("%d\t",ptr->info);

        ptr=ptr->link;

    }

    printf("\nEnter the location where you have to delete:");

    scanf("%d",&loc);

        ptr=first;

    while(ptr->info!=loc)

    {

        cpt=ptr;

        ptr=ptr->link;

        

    }

    cpt->link=ptr->link;

    free(ptr);

}

}

while(s<9);

return 0;

}