Singly_Linked_List.cpp

#include<stdio.h>
#include<stdlib.h>
#define NULL 0

 typedef struct list
 {
 int no;
 struct list *next;
}LIST;

LIST *p,*t,*h,*y,*ptr,*pt;

void create( void );
void insert( void );
void delet( void );
void display ( void );
int j,pos,k=1,count;     

int main()
{
 int n,i=1,opt;
 p = NULL;
 printf("%d/n",sizeof(LIST));
 printf( " /nEnter the no of nodes : " );
 scanf( "%d",&n );
 count = n;
 while( i <= n)
 { 
  create();
  i++;
 }
 printf("\nEnter your option:\n");
 printf("1.Insert \t 2.Delete \t 3.Display \t 4.Exit\n");
 do
 {
  scanf("%d",&opt);
  switch( opt )
  {
   case 1:
    insert();
	count++;
	break;
   case 2:
delet();
count--;
if ( count == 0 )
{
printf("\n List is empty\n");
}
break;

case 3:
printf("List elements are:\n");
display();
break;
}
printf("\nEnter your option \n");
}while( opt != 4 );
return 0;
}

void create ( )
{
 if( p== NULL )
{
p = ( LIST * ) malloc ( sizeof ( LIST ) );
printf( "Enter the element:\n" );
scanf( "%d",&p->no );
p->next = NULL;
h = p;
}
 else
{
t= ( LIST * ) malloc (sizeof( LIST ));
printf( "\nEnter the element" );
scanf( "%d",&t->no );
t->next = NULL;
p->next = t;
p = t;
}
}

void insert()
{
 t=h;
p = ( LIST * ) malloc ( sizeof(LIST) );
printf("Enter the element to be inserted:\n");
scanf("%d",&p->no);
printf("Enter the position to insert:\n");
scanf( "%d",&pos );
if( pos == 1 )
{
h = p;
h->next = t;
}
else
{
for(j=1;j<(pos-1);j++)
t = t->next;
p->next = t->next;
t->next = p;
t=p;
}
}

void delet(){
printf("Enter the position to delete:\n");
scanf( "%d",&pos );
if( pos == 1 )
{
h = h->next ;
}
 else
{
t= h;
for(j=1;j<(pos-1);j++)
t = t->next;
pt=t->next->next;
free(t->next);
t->next= pt;
}
}

void display()
{
t= h;
while( t->next != NULL )
{
printf("\t%d",t->no);
t = t->next;
}
printf( "\t %d\t",t->no );
}