#include <stdio.h>
#include <stdlib.h> // 包含了 qsort 函数所需的头文件
#include <string.h> // 包含了字符串处理函数所需的头文件

// 学生信息的结构体
struct Student {
    int student_id;
    int class_id;
    char name[50];
    float score1;
    float score2;
    float score3;
};

// 比较函数，用于排序
int compareStudents(const void *a, const void *b) {
    struct Student *student1 = (struct Student *)a;
    struct Student *student2 = (struct Student *)b;

    if (student1->class_id != student2->class_id) {
        return student1->class_id - student2->class_id;
    } else {
        float total_score1 = student1->score1 + student1->score2 + student1->score3;
        float total_score2 = student2->score1 + student2->score2 + student2->score3;
        return total_score2 - total_score1;
    }
}

int main() {
    struct Student students[100];
    int num_students = 3;  // 初始有3个学生信息

    // 初始化已有学生信息
    students[0] = (struct Student){10001, 11, "Zhang", 99.5, 88.5, 89.5};
    students[1] = (struct Student){10002, 12, "Yang", 77.9, 56.5, 87.5};
    students[2] = (struct Student){10003, 11, "Liang", 92.5, 99.0, 60.5};

    // 对已有学生信息进行排序
    qsort(students, num_students, sizeof(struct Student), compareStudents);

    // 输入待修改学生的信息
    struct Student modified_student;
    printf("输入待修改学生的信息（学号 班级 姓名 成绩1 成绩2 成绩3）：");
    scanf("%d %d %s %f %f %f", &modified_student.student_id, &modified_student.class_id, modified_student.name, &modified_student.score1, &modified_student.score2, &modified_student.score3);

    // 检查学号是否存在，如果不存在，输出原有三个学生信息并退出程序
    int found = 0;
    for (int i = 0; i < num_students; i++) {
        if (modified_student.student_id == students[i].student_id) {
            found = 1;
            students[i] = modified_student;
            break;
        }
    }

    if (!found) {
        printf("该学生信息不存在，输出原有三个学生信息并退出程序：\n");
        for (int i = 0; i < num_students; i++) {
            printf("%d %d %s %.1f %.1f %.1f\n", students[i].student_id, students[i].class_id, students[i].name, students[i].score1, students[i].score2, students[i].score3);
        }
        return 0;
    }

    // 对新数据进行排序
    qsort(students, num_students, sizeof(struct Student), compareStudents);

    // 输出学生信息
    for (int i = 0; i < num_students; i++) {
        if (i == 0 || students[i].class_id != students[i - 1].class_id) {
            printf("%d %d %s %.1f %.1f %.1f", students[i].student_id, students[i].class_id, students[i].name, students[i].score1, students[i].score2, students[i].score3);
        } else {
            printf("   %d %s %.1f %.1f %.1f", students[i].student_id, students[i].name, students[i].score1, students[i].score2, students[i].score3);
        }

        if (i == num_students - 1) {
            printf(" modified\n");
        } else {
            printf("\n");
        }
    }

    return 0;
}