C Program to Create a Linked List and Find its Length

#include<stdio.h>
#include<conio.h>
#include<alloc.h>
#define newnode (struct node*) malloc(sizeof(struct node))

struct node
{
 int data;
 struct node *next;
};

struct node *create();

int main()
{
 struct node *f;
 int len;
 f = NULL;
 clrscr();

 f = create();
 len = calc_len(f);
 printf("\n Length = %d",len);
 getch();
return 0;
}

struct node *create()
{
 struct node *f,*c,*p;
 int data1;
 f = NULL;
 printf("\n Enter data ( use 0 to exit ) : ");
 scanf("%d",&data1);
 while( data1 != 0 )
 {
  c = newnode;
  if( c == NULL)
  {
   printf("\n Insuf. mem. ");
   exit(0);
  }
  c->data = data1;
  c->next = NULL;
  if( f== NULL)
   f = c;
  else
   p->next = c;
   p = c;
   printf("\n Enter data ( use 0 to exit ) : ");
   scanf("%d",&data1);
 }
 return(f);
} 
int calc_len(struct node *f)
{
 int len=0;
 struct node *t;
 if( f == NULL)
 return(0);
 t = f;
 while( t != NULL )
 {
  len++;
  t = t->next;
 }
 printf("Length = %d\n",len);
 return(len);
}