C语言动态链表建立问题

Question

#include
#include
#define LEN sizeof(struct Student)

int n = 0;//记录数据的个数

struct Student
{
    int number;
    int score;
    struct Student *next;
};


int main()
{
    struct Student *creat(void);
    void print(struct Student *p);
    struct Student *p;
    p = creat();
    print(p);
    return 0;
}


struct Student *creat(void)
{
    struct Student *p1,*p2;
    struct Student *head = NULL;
    p1 = p2 = (struct Student *)malloc(LEN);
    printf("please enter Students' informations(number & score:)");
    scanf("%d %d",&p1->number,&p1->score);//get
    while(p1->number != 0)
    {
        n += 1;
        if(n==1)head = p1;
        else p2->next = p1;
        p2 = p1;
        printf("please enter Students' informations(number &score):");
        scanf("%d %d",p1->number,p1->score);
        p1 = (struct Student*)malloc(LEN);

    }
   p2->next = NULL;
   return (head);
};


void print(struct Student *p)
{
    printf("their informations as follows:\n");
    while(p->number!=0)
    {
        printf("%d %d",p->number,p->score);
        p = p->next;
    }
}

代码如上，运行后输入第二个数据后显示“该内存不能为written”,用的是CODEBLOCKS。卡在这一天了，求解答，万分感谢~

Answer 1

while(p1->number != 0) { n += 1; if(n==1)head = p1; else p2->next = p1; p2 = p1; printf("please enter Students' informations(number &score):"); scanf("%d %d",p1->number,p1->score); p1 = (struct Student*)malloc(LEN); }

检查这里的scanf函数

Answer 2

你定义的create函数怎么是个指针？

Answer 3

 #define _CRT_SECURE_NO_WARNINGS
#include <stdio.h>
#define LEN sizeof(struct Student)
int n = 0;//记录数据的个数
struct Student
{
    int number;
    int score;
    struct Student *next;
};


int main()
{
    struct Student *creat(void);
    void print(struct Student *p);
    struct Student *p;
    p = creat();
    print(p);
    return 0;
}


struct Student *creat(void)
{
    struct Student *p1, *p2;
    struct Student *head = NULL;
    p1 = p2 = (struct Student *)malloc(LEN);
    printf("please enter Students' informations(number & score:)");
    scanf("%d %d", &p1->number, &p1->score);//get
    while (p1->number != 0)
    {
        n += 1;
        if (n == 1)
            head = p1;
        else
            p2->next = p1;
        p2 = p1;
        printf("please enter Students' informations(number &score):");
        p1 = (struct Student*)malloc(LEN);
        scanf("%d %d", &p1->number, &p1->score);


    }
    p2->next = NULL;
    return (head);
};


void print(struct Student *p)
{
    printf("their informations as follows:\n");
    while (p!= NULL)
    {
        printf("%d %d\n", p->number, p->score);
        p = p->next;
    }
}

Answer 4

1：

  p1 = (struct Student*)malloc(LEN);
        scanf("%d %d", &p1->number, &p1->score);

2：

  while (p!= NULL)
    {
        printf("%d %d\n", p->number, p->score);
        p = p->next;
    }