前言
彩笔写个大作业每个功能都要卡好久。唉，带专人太难了，呜呜呜。
吐槽：chatgpt不靠谱，我改了一下，让它能跑起来。
程序要求
1. 输入学生姓名，成绩（连续两个空格换行），并保存在./score.txt中。
2. 将./score.txt中的成绩由大到小排序，赋上排名，覆盖原有文件。
3. 按成绩由大到小打印。
代码
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#define MAX_STUDENTS 100
//成绩写入，读取排名
struct student {char name[20];int score;int rank;
};int compare_students(const void *a, const void *b){struct student *s1 = (struct student *)a;struct student *s2 = (struct student *)b;return s2->score - s1->score;//后面大于前面就置换
}int main() {struct student students[MAX_STUDENTS],a[MAX_STUDENTS];
//不知道为啥，上面的结构体赋初值（0）会导致没法结束输入int num_students = 0; int i=0,j;char ch;int hnum;//写 FILE *file = fopen(".//score.txt", "a+");if(file==NULL){file=fopen(".//score.txt","wb+");}while(i<10){int w=0;//每行第几字符 while((ch=getchar())!=' '){if(ch=='\n'){hnum+=1;}else{hnum=0;//不是连续的两个\n就清零 }if(hnum==2){break;}else if(hnum==1){continue;//防止数组存入\n} a[i].name[w]=ch;w++;}a[i].name[w]='\0';//数组末尾补0 if(hnum==2){break;} scanf("%d",&a[i].score);a[i].rank=0;i++;}for(j=0;j<i;j++){fwrite(&a[j],1,sizeof(struct student),file);}fclose(file);
//下面开始排序 file = fopen(".//score.txt", "r");if(file==NULL){printf("Unable to open file.\n");}
//文件读操作(fread)，必须先读一次再接while循环判断是否到文件末尾，不然下面for会多一次fread(&students[num_students], sizeof(struct student), 1, file);while(!feof(file)){num_students++;fread(&students[num_students], sizeof(struct student), 1, file);}fclose(file);qsort(students, num_students, sizeof(struct student), compare_students);//从大到小排序 for (i = 0; i < num_students; i++) {students[i].rank = i + 1;}file = fopen(".//score.txt", "w+");if (file == NULL) {printf("Unable to open file.\n");return 1;}for (i = 0; i < num_students; i++) {fwrite(&students[i],1,sizeof(struct student),file);}fclose(file);
//打印排名 file = fopen(".//score.txt", "r");printf("Students sorted by rank:\n");fread(&students[j],1,sizeof(struct student),file);while (!feof(file)) { printf("%d. %s: %d\n", students[j].rank, students[j].name, students[j].score);fread(&students[j],1,sizeof(struct student),file);}fclose(file);return 0;
}
