Q. Write an algorithm INSERT which takes a pointer to a sorted list and a pointer to a node and inserts the node into its correct position or place in the list. 

Ans:

/* structure containing  the data part and link part */

struct node

{

int data ;

struct node *link ;

} ;

/* Following the inserts node to an ascending order linked list

*/

void INSERT ( struct node **q, int num )

{

struct node *r, *temp = *q ;

r = malloc ( sizeof ( struct node ) ) ;

r -> data = num ;

/* if list is empty or if new node is to be inserted before the first node */

if ( *q == NULL || ( *q ) -> data > num )

{

*q = r ;

( *q ) -> link = temp ;

}

else

{

/* traverse the entire linked list to search or found the position to insert the

new node */

while ( temp != NULL )

{

if ( temp -> data <= num && ( temp -> link -> data > num ||

temp -> link == NULL ))

{

r -> link = temp -> link ;

temp -> link = r ;

return ;

}

temp = temp -> link ; /* go to the next node */ }

}

}