双向链表插入删除操作

#include <stdio.h>
#include <malloc.h>

typedef struct _DULNODE_
{
    int num;
    struct _DULNODE_ *prior;
    struct _DULNODE_ *next;
}DULNODE,*DULLINK;

DULLINK Creat_DulList(void)
{
    DULLINK head=NULL,pcurrent=NULL,ptemp=NULL;
    int num=0,total=0;

    do
    {
        printf("please input the number: \n");
        scanf("%d",&total);
        if( total == 0 )
            printf("sorry,the number is error!\n");
        else
            printf("\n");

    }while( total == 0 );

    while(num<total)
    {
        num=num+1;

        pcurrent=(DULLINK)malloc(sizeof(DULNODE));
        if( pcurrent==NULL )
        {
            printf("malloc error,please check it!\n");
            break;
        }
        else
            pcurrent->num=num;

        if( num == 1)
        {
            head=pcurrent;
            pcurrent->prior=NULL;
        }
        else
        {
            ptemp->next=pcurrent;
            pcurrent->prior=ptemp;
        }

        ptemp=pcurrent;
    }
    ptemp->next=NULL;
    return(head);
}

void Print_DulInfo(DULLINK head)
{
    DULLINK ptemp;

    if( head == NULL)
    {
        printf("error:have no data!\n");
        return;
    }

    ptemp=head;
    while(ptemp)
    {
        printf("num: %d\n",ptemp->num);
        ptemp=ptemp->next;
    }

    return;
}

DULLINK Insert_DulList(DULLINK head,DULLINK node)
{
    DULLINK pcurrent=NULL,pinsert=NULL;

    pcurrent=head;
    pinsert=node;

    if( head==NULL )
    {
        head=node;
        head->prior=head->next=NULL;
    }
    else
    {
        while(( pinsert->num>pcurrent->num )&&( pcurrent->next!=NULL ))
        {
            pcurrent=pcurrent->next;
        }

        if( pinsert->num<=pcurrent->num )
        {
            if( pcurrent==head)
            {
                head->prior=pinsert;
                pinsert->next=head;
                pinsert->prior=NULL;
                head=pinsert;
            }
            else
            {
                pcurrent->prior->next=pinsert;
                pinsert->prior=pcurrent->prior;
                pinsert->next=pcurrent;
                pcurrent->prior=pinsert;
            }
        }
        else
        {
            pcurrent->next=pinsert;
            pinsert->prior=pcurrent;
            pinsert->next=NULL;
        }

    }

    return(head);
}

DULLINK Delete_DulList(DULLINK head,int num)
{
    DULLINK pcurrent=NULL;

    pcurrent=head;

    if( head==NULL )
    {
        printf("error:please check the data!\n");
        return(NULL);
    }
    else
    {
        while( (num!=pcurrent->num)&&(pcurrent->next!=NULL) )
            pcurrent=pcurrent->next;

        if(num==pcurrent->num)
        {
            if( pcurrent==head )
            {
                pcurrent->next->prior=NULL;
                head=pcurrent->next;
            }
            else if(pcurrent->next==NULL)
            {
                pcurrent->prior->next=NULL;
            }
            else
            {
                pcurrent->prior->next=pcurrent->next;
                pcurrent->next->prior=pcurrent->prior;
            }

            free(pcurrent);

            printf("the num have been deletea is: %d\n",num);
        }
        else
            printf("can not find the num: %d\n",num);
    }

    return(head);
}

int main(int argc,char **argv)
{
    DULLINK head,ptemp;
    int num=0;

    head=Creat_DulList();
    Print_DulInfo(head);

    printf("please input the delete num:\n");
    scanf("%d",&num);
    head=Delete_DulList(head, num);
    Print_DulInfo(head);

    ptemp=(DULLINK)malloc(sizeof(DULNODE));
    printf("please input the add num:\n");
    scanf("%d",&num);
    ptemp->num=num;
    head=Insert_DulList(head,ptemp);
    Print_DulInfo(head);

    return 0;
}