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/*

 * author: lx

 * date: 2011-09-08

 * brief: the interface of list

 * file: llist.c

 */



#include <stdio.h>

#include <stdlib.h>

#include "llist.h"



int

insert_list( register Node **linkp, int new_value )

{

        register Node *current;

        register Node *new;



        while ( ( current = *linkp ) != NULL &&

                current->value < new_value )

                linkp = &current->link;



        new = ( Node* )malloc( sizeof( Node ) );

        if ( new == NULL )

                return FALSE;

        new->value = new_value;



        new->link = current;

        *linkp = new;



        return TRUE;

}



Node*

search_list( register Node* L, int k )

{

        Node* x = L;



        while ( x != NULL && x->value != k )

                x = x->link;



        return x;

}





int

delate_list( register Node** L, int k )

{

        Node *d = NULL;



        if ( ( d = search_list( *L, k ) ) == NULL )

                return FALSE;



        /*

         * find the predecessor of the value k.

         */

        Node **x = L ;

        Node *p = NULL;

        while( x != NULL )

        {

                if ( ( *x )->value != k )

                {



                        p = *x;

                        x = &((*x)->link);

                }

                else

                {

                        if ( x == L )

                                *L = (*L)->link;

                        return TRUE;

                }

        }



        p->link = (*x)->link;



        free( *x );



        return TRUE;

}

　　头文件：

/*

 * author: lx

 * date: 2011-09-08

 * brief: the interface of list 

 * file: llist.h

 */



#define FALSE 0

#define TRUE 1



typedef struct NODE

{

        struct NODE *link;

        int     value;

}Node;





/*

 * add a element into list

 *

 * return value: 0 is right, -1 is error. 

 */

int

insert_list( register Node**, int );





/*

 * search a element in the list.

 *

 * return the pointer of Node if find. else return NULL

 *

 */

Node*

search_list( register Node*, int );



/*

 * delete a element in the list.

 *

 * returen value: 0 is right, -1 is error.

 */

int

delate_list( register Node**, int );

　　

例子：

#include <stdio.h>

#include <stdlib.h>

#include "llist.h"



int

main( void )

{



        Node *p = ( Node* )malloc( sizeof( Node ) );

        if ( p == NULL )

                return FALSE;



        p->link = NULL;

        p->value = 1;





        printf( "insert some elements after 1......\n" );



        insert_list( &p, 2 );

        insert_list( &p, 3 );







        Node *plist = p;

        while( plist != NULL )

        {

                printf( "value is %d\n", plist->value );

                plist = plist->link;

        }







        delate_list( &p, 1 );



        printf( "after delate.....\n" );

        plist = p;

        while( plist != NULL )

        {

                printf( "value is %d\n", plist->value );

                plist = plist->link;

        }



        exit( 0 );

}