在C语言读txt文件的数据时出现错误

问题遇到的现象和发生背景

问题相关代码，请勿粘贴截图

#include <stdio.h>
struct student
{
    int ID;
    char name[10];
    int grade[3];
};
int getinputfromfile(char *filename,struct student *s,int maxnum)
{
    FILE* fp=fopen(filename,"r");
    if(fp==NULL){
        printf("error");
        return 0;
    }
    int i,j,k;
    for(i=0;i<maxnum;i++){
            if(feof(fp)){
                return i;
            }
            fscanf(fp,"%d",&(s + i)->ID);
            fscanf(fp,"%s",s[i].name);
            for(k=0;k<3;k++){
                fscanf(fp,"%d",&s[i].grade[k]);
                }
        }
    return maxnum;
}

int main()
{
    int n,maxnum;
    printf("请输入最大学生数:");
    scanf("%d",&maxnum); 
    struct student *s;
    n=getinputfromfile("test.txt",s,maxnum);
    printf("学生数为："); 
    printf("%d",n);
}

运行结果及报错内容

调试到fscanf(fp,"%d",&(s + i)->ID);时开始出错

txt文件中的数据是
1
zz
22
22
33
2
ss
44
55
66
3
ee
77
8
8

我的解答思路和尝试过的方法

我想要达到的结果

struct student *s; 定义s时没有初始化内存。

#include <stdio.h>
struct student
{
    int ID;
    char name[10];
    int grade[3];
};
int getinputfromfile(char* filename, struct student* s, int maxnum)
{
    FILE* fp = fopen(filename, "r");
    if (fp == NULL) {
        printf("error");
        return 0;
    }
    int i, j, k;
    for (i = 0; i < maxnum; i++) {
        if (feof(fp)) {
            return i;
        }
        fscanf(fp, "%d", &(s + i)->ID);
        fscanf(fp, "%s", s[i].name);
        for (k = 0; k < 3; k++) {
            fscanf(fp, "%d", &s[i].grade[k]);
        }
    }
    return maxnum;
}
int main()
{
    int n, maxnum;
    printf("请输入最大学生数:");
    scanf("%d", &maxnum);
    struct student* s = new student;;
    n = getinputfromfile("test.txt", s, maxnum);
    printf("学生数为：");
    printf("%d", n);
}