主要内容：该系统实现对学生成绩的批量录入、修改、查询、浏览等功能。具体要求如下： 学生信息包括：学号、姓名、入学年月、4门课的成绩等8个成员，试设计学生成绩管理系统，使之能提供以下功能： 1、信息录入：录入每一位学生信息（包括学号、姓名、入学年月和4门课的成绩）； 2、信息浏览：输出系统内所有学生的信息； 3、成绩修改：输入学号，修改该生某一门课的成绩； 4、分类查询：按学号或姓名查找学生，输出学生的成绩单； 5、统计学生总成绩：计算每个学生的总分及平均分，并根据学生的平均成绩进行排序；6、统计每门课程的成绩：计算每一门课程学生的及格率、优秀率等。的c语言代码

以下是一个简单的C语言代码示例，实现了上述要求：

#include <stdio.h>
#include <string.h>

#define MAX_STUDENTS 100
#define MAX_NAME_LEN 50

typedef struct {
    int id;
    char name[MAX_NAME_LEN];
    char enroll_date[20];
    int scores[4];
    int total_score;
    float avg_score;
} Student;

Student students[MAX_STUDENTS];
int num_students = 0;

void add_student() {
    if (num_students >= MAX_STUDENTS) {
        printf("Too many students\n");
        return;
    }
    Student *s = &students[num_students];
    printf("Enter student ID: ");
    scanf("%d", &s->id);
    printf("Enter student name: ");
    scanf("%s", s->name);
    printf("Enter enrollment date: ");
    scanf("%s", s->enroll_date);
    printf("Enter scores for 4 courses: ");
    for (int i = 0; i < 4; i++) {
        scanf("%d", &s->scores[i]);
        s->total_score += s->scores[i];
    }
    s->avg_score = (float)s->total_score / 4.0;
    num_students++;
}

void view_students() {
    printf("ID\tName\tEnroll Date\tCourse 1\tCourse 2\tCourse 3\tCourse 4\tTotal Score\tAvg Score\n");
    for (int i = 0; i < num_students; i++) {
        Student *s = &students[i];
        printf("%d\t%s\t%s\t", s->id, s->name, s->enroll_date);
        for (int j = 0; j < 4; j++) {
            printf("%d\t\t", s->scores[j]);
        }
        printf("%d\t\t%.2f\n", s->total_score, s->avg_score);
    }
}

void update_score() {
    int id, course, score;
    printf("Enter student ID: ");
    scanf("%d", &id);
    printf("Enter course number (1-4): ");
    scanf("%d", &course);
    printf("Enter new score: ");
    scanf("%d", &score);
    for (int i = 0; i < num_students; i++) {
        if (students[i].id == id) {
            students[i].scores[course-1] = score;
            students[i].total_score = 0;
            for (int j = 0; j < 4; j++) {
                students[i].total_score += students[i].scores[j];
            }
            students[i].avg_score = (float)students[i].total_score / 4.0;
            printf("Score updated\n");
            return;
        }
    }
    printf("Student not found\n");
}

void search_students() {
    int choice;
    printf("Search by:\n1. ID\n2. Name\n");
    scanf("%d", &choice);
    if (choice == 1) {
        int id;
        printf("Enter student ID: ");
        scanf("%d", &id);
        for (int i = 0; i < num_students; i++) {
            if (students[i].id == id) {
                Student *s = &students[i];
                printf("Name: %s\nEnroll Date: %s\nCourse 1: %d\nCourse 2: %d\nCourse 3: %d\nCourse 4: %d\nTotal Score: %d\nAvg Score: %.2f\n", s->name, s->enroll_date, s->scores[0], s->scores[1], s->scores[2], s->scores[3], s->total_score, s->avg_score);
                return;
            }
        }
        printf("Student not found\n");
    } else if (choice == 2) {
        char name[MAX_NAME_LEN];
        printf("Enter student name: ");
        scanf("%s", name);
        for (int i = 0; i < num_students; i++) {
            if (strcmp(students[i].name, name) == 0) {
                Student *s = &students[i];
                printf("ID: %d\nEnroll Date: %s\nCourse 1: %d\nCourse 2: %d\nCourse 3: %d\nCourse 4: %d\nTotal Score: %d\nAvg Score: %.2f\n", s->id, s->enroll_date, s->scores[0], s->scores[1], s->scores[2], s->scores[3], s->total_score, s->avg_score);
                return;
            }
        }
        printf("Student not found\n");
    }
}

void sort_students() {
    for (int i = 0; i < num_students; i++) {
        int max_idx = i;
        for (int j = i+1; j < num_students; j++) {
            if (students[j].avg_score > students[max_idx].avg_score) {
                max_idx = j;
            }
        }
        if (max_idx != i) {
            Student temp = students[max_idx];
            students[max_idx] = students[i];
            students[i] = temp;
        }
    }
    printf("Students sorted by average score:\n");
    view_students();
}

void stats_by_course() {
    for (int i = 0; i < 4; i++) {
        int pass_count = 0;
        int excellent_count = 0;
        for (int j = 0; j < num_students; j++) {
            if (students[j].scores[i] >= 60) {
                pass_count++;
            }
            if (students[j].scores[i] >= 90) {
                excellent_count++;
            }
        }
        printf("Course %d:\nPass Rate: %.2f%%\nExcellent Rate: %.2f%%\n", i+1, (float)pass_count / num_students * 100.0, (float)excellent_count / num_students * 100.0);
    }
}

int main() {
    int choice;
    while (1) {
        printf("Select an option:\n1. Add student\n2. View students\n3. Update score\n4. Search students\n5. Sort students by average score\n6. View stats by course\n7. Exit\n");
        scanf("%d", &choice);
        switch (choice) {
            case 1:
                add_student();
                break;
            case 2:
                view_students();
                break;
            case 3:
                update_score();
                break;
            case 4:
                search_students();
                break;
            case 5:
                sort_students();
                break;
            case 6:
                stats_by_course();
                break;
            case 7:
                return 0;
            default:
                printf("Invalid choice\n");
                break;
        }
    }
    return 0;
}

请注意，这只是一个基本的实现，可能需要根据具体需求进行修改和改进。