Write C program to Delete nodes at Beginning, Middle and at End using functions in Single Linked List

Write C program to Delete nodes at Beginning, Middle and at End using functions

  #include <stdio.h>

  struct node

  {

   int data;

   struct node*link;

  };

  struct node * getnode()

  {

    struct node *p;

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

    printf("enter data into the node:");

    scanf("%d",&p->data);

    p->link=NULL;

    return p;

  }

  int  countnodes(struct node *f)

   {

    struct node *temp;

    int ct=0;

    temp=f;

    while(temp!=NULL)

    {

      ct++;

      temp=temp->link;

    }

    return ct;

  }

  struct node * createnodes()

  {

    struct node *first,*t,*temp;

    char ch='Y';

    int ct=0;

    while(ch=='Y')

    {

      if(ct==0)

      {

       first=getnode();

       ct++;

       temp=first;

      }

      else

      {

       temp=first;

       while(temp->link!=NULL)

       {

            temp=temp->link;

       }

       t=getnode();

       temp->link=t;

       temp=t;

      }

      printf("do you want to continue:");

      fflush(stdin);

      ch=getchar();

     }

     return first;

   }

   void displaylist (struct node *f)

   {

     struct node *temp;

     temp=f;

     while(temp!=NULL)

     {

      printf("%d-->",temp->data);

      temp=temp->link;

     }

     printf("NULL\n");

  }

/* struct node * deletefirstnode(struct node *first)

  {

     struct node *temp;

     temp=first;

     first=temp->link;

     free(temp);

   return first;

  }

  struct node * deletelastnode(struct node *first)

   {

    struct node *temp,*temp1;

    temp=first;

    temp1=first;

    while(temp->link!=NULL)

    {

     temp=temp->link;

    }

    while(temp1->link!=temp)

    {

     temp1=temp1->link;

    }

     temp1->link=NULL;

     free(temp);

     return first;

   }

   struct node *deletemiddlenode(struct node *first, int pos)

   {

     struct node *temp,*temp1;

     int i;

     temp=first;

     temp1=first;

     for(i=1;i<pos;i++)

     {

      temp=temp->link;

     }

     for(i=1;i<pos-1;i++)

     {

      temp1=temp1->link;

     }

     temp1->link=temp->link;

     free(temp);

     return first;

    }    */

    struct node * deletenodes(struct node *f,int pos)

    {

     struct node *t,*t1;

     int ct,i;

     ct=countnodes(f);

     t=f;

     t1=f;

     if(ct<pos)

     {

      printf("please cheak number of nodes & position to deleted\n");

     }

     else if(pos==1)

     {

      f=f->link;

      free(t);

     }

     else if(pos==ct)

     {

      for(i=1;i<pos;i++)

      {

       t=t->link;

      }

      for(i=1;i<pos-1;i++)

      {

       t1=t1->link;

      }

      t1->link=NULL;

      free(t);

     }

     else

     {

      for(i=1;i<pos;i++)

      {

       t=t->link;

      }

      for(i=1;i<pos-1;i++)

      {

       t1=t1->link;

      }

      t1->link=t->link;

      free(t);

     }

     return f;

   }

   void main()

   {

     int ct,n;

     struct node *first;

     clrscr();

     first=createnodes();

     displaylist(first);

     ct=countnodes(first);

     printf("number of nodes=%d\n",ct);

    /* first=deletefirstnode(first);

     displaylist(first);

     first=deletelastnode(first);

     displaylist(first);

     first=deletemiddlenode(first,4);*/

     printf("enter which node to be deleted\n");

     scanf("%d",&n);

     first=deletenodes(first,n);

     displaylist(first);

     getch();

  }