#include<stdio.h>
#include<stdlib.h>
#include<fstream>
using namespace std;

struct students
{
    char no[20];
    char name[20];
    char score;
    struct students *next;
   
};
int main(){
   
    FILE *fp=NULL;
    students *p,*p1;
    students *head;
    head = (students *)malloc(sizeof(students));
    head->next = NULL;
    if((fp = fopen("student.txt","rb"))==NULL)
    {
        printf("cannot open flie\n");
        return 0;
    }
    while(!feof(fp))
    {
        p = (students *)malloc(sizeof(students));
        fread(p,sizeof(students),1,fp);
        
        
        if(head==NULL) {
            head=p;
            p->next=NULL;
        }
        else{
            p1=head;
            while(p1->next!=NULL){
                p1=p1->next;
            }
        }
        

        p1->next = p;
        p->next = NULL;
        
    }
    fclose(fp);
   
    while (head != NULL) //输出链表中内容,验证数据已经写入到链表
    {
        printf ("s%  s%   d% ",head->no,head->name,head->score);
        head = head->next;
    }
    printf ("数据写入链表成功\n");
   
    return 0;
}

关键是我不知道怎样改

我是直接新建txt 输入的 1 2 3 4 5 6  保存