C语言-文件

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

struct student{
    char id[11];
    double mid ;
    double end ;
    double sum ;
};

int main()
{
    FILE *fp;
    int n,i;
    struct student stu[100];
    i=0;
    scanf("%d",&n);
    fp=fopen("d:\\list.txt","w");
    fprintf(fp,"%s","学号        期中   期末   综合\n");
    while(i<n){
        scanf("%s",stu[i].id);
        scanf("%lf",&stu[i].mid);
        scanf("%lf",&stu[i].end);
        stu[i].sum=stu[i].mid*0.3+stu[i].end*0.7;
        i++;
    }
    i=0;
    while(i<n){
    fprintf(fp,"%s",stu[i].id);
    fprintf(fp,"%5.0lf",stu[i].mid);
    fprintf(fp,"%7.0lf",stu[i].end);
    fprintf(fp,"%7.0lf",stu[i].sum);
    fprintf(fp,"%c",'\n');
    i++;
    }
    fclose(fp);
    return 0;
}