[C++知识库]链表的增删该查

#include<stdio.h>
#include <stdlib.h>

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

/*打印数据*/
void printLink(struct test *head)
{
    int count = 0;
    while(head != NULL)
    {
        count++;
        printf("NO.%d,data=%d\n",count,head->data);
        head = head->next;
    }
    printf("total number=%d\n",count);
}

/*从前方插入*/
struct test * inserDataFromForward(struct test *head,int data,struct test *new)
{
    struct test *p=head;
    if(head->data == data)
    {
        new->next = head;
        return new;
    }
    while(head->next != NULL) 
    {
        if(head->next->data ==data)
        {
           new->next = head->next;
           head->next = new;
           return p;
        }
        head = head->next;
    }
    return p;
}

/*从后方插入*/
int inserDataFromBehind(struct test *head,int data,struct test *new)
{
    while(head != NULL) 
    {
        if(head->data == data)
        {
            new->next = head->next;
            head->next = new;
        }
        head = head->next;
    }
    return 0;
}

/*删除数据*/
struct test * deleteData(struct test *head,struct test *destData)
{
    struct test *p =head;
    if(head->data == destData->data)
    {
        head = head->next;
        free(p);
        return head;
    }
    while(p->next!=NULL)
    {
        if(p->next->data == destData->data)
        {
            struct test * tmp = p->next;
            p->next = p->next->next;
            free(tmp);
            return head;
        }
        p = p->next;
    }
    return head;

}
/*增加单个数据*/
struct test *addData(struct test* head,struct test* new)
{
    if(head == NULL)
    {
        head = new;
    }
    else
    {
        new->next = head;
        head = new;
    }
    return head;
}

/*尾差法创建链表*/
struct test * createLinkFromTail(struct test* head )
{
    struct test *new = NULL;
    struct test * p=NULL;
    while(1)
    {
        p = head;
        new = (struct test *)malloc(sizeof(struct test));
        printf("please input a intger\n");
        scanf("%d",&(new->data));
        if(new->data == 0)
        {
            break;
        }
        if(head == NULL)
        {
            head =new;
            new->next =NULL;
        }
        else
        {
            while(p->next !=NULL)
            {
                p = p->next;
            }
            p->next = new;
            new->next =NULL;
        }
    }
    return head;
}
/*头插法创建链表*/
struct test * createLinkFromHead(struct test* head )
{
    struct test *new = NULL;
    while(1)
    {
        new = (struct test *)malloc(sizeof(struct test));
        printf("please input a intger\n");
        scanf("%d",&(new->data));
        if(new->data == 0)
        {
            break;
        }

        head = addData(head,new);

    }
    return head ;
}

int main()
{
    struct test *head = NULL;
    struct test New = {100,NULL};
   // head = createLinkFromHead(head);
    head = createLinkFromTail(head);
    printLink(head);
   // head = deleteData(head,&New);
   // inserDataFromBehind(head,3,&New);
   // head= inserDataFromForward(head,3,&New);
    //printLink(head);

	return 0;
}