用c语言实现功能要求 基本要求：(1)试设计一个学生成绩信息管理系统，使之能提供以下功能： (2)按学期、班级完成对学生成绩的录入功能、修改(3)按班级统计学生的成绩，求学生的总分及平均分，并排序(4)能查询学生成绩，不及格科目及学生名单(5)按班级输出学生的成绩单

好的，我会尽力回答你的问题。

首先，你需要设计一个学生成绩信息管理系统，这个系统需要能够提供以下功能：

1. 录入学生成绩：可以按照学期、班级来录入学生成绩，也可以修改已有的学生成绩信息。

2. 统计学生成绩：可以按照班级来统计学生成绩，包括学生的总分、平均分，并且需要进行排序。

3. 查询学生成绩：可以查询学生成绩，包括不及格科目和学生名单。

4. 输出学生成绩单：可以按照班级来输出学生成绩单。

为了实现这些功能，你可以使用 C 语言来编写代码。下面是一个简单的实现：

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

#define MAX_CLASS_SIZE 100
#define MAX_NAME_LENGTH 20
#define MAX_SUBJECTS 10

typedef struct {
    char name[MAX_NAME_LENGTH];
    int score[MAX_SUBJECTS];
    int total;
    float average;
} student;

typedef struct {
    char name[MAX_NAME_LENGTH];
    student students[MAX_CLASS_SIZE];
    int size;
} class;

class classes[MAX_CLASS_SIZE];
int num_classes = 0;

void add_class() {
    printf("Enter class name: ");
    scanf("%s", classes[num_classes].name);
    classes[num_classes].size = 0;
    num_classes++;
}

void add_student() {
    char class_name[MAX_NAME_LENGTH];
    int i, j;

    printf("Enter class name: ");
    scanf("%s", class_name);

    for (i = 0; i < num_classes; i++) {
        if (strcmp(classes[i].name, class_name) == 0) {
            printf("Enter student name: ");
            scanf("%s", classes[i].students[classes[i].size].name);
            printf("Enter student scores:\n");
            for (j = 0; j < MAX_SUBJECTS; j++) {
                printf("Subject %d: ", j+1);
                scanf("%d", &classes[i].students[classes[i].size].score[j]);
                classes[i].students[classes[i].size].total += classes[i].students[classes[i].size].score[j];
            }
            classes[i].students[classes[i].size].average = (float) classes[i].students[classes[i].size].total / MAX_SUBJECTS;
            classes[i].size++;
            printf("Student added.\n");
            return;
        }
    }

    printf("Class not found.\n");
}

void modify_student() {
    char class_name[MAX_NAME_LENGTH], student_name[MAX_NAME_LENGTH];
    int i, j;

    printf("Enter class name: ");
    scanf("%s", class_name);

    for (i = 0; i < num_classes; i++) {
        if (strcmp(classes[i].name, class_name) == 0) {
            printf("Enter student name: ");
            scanf("%s", student_name);
            for (j = 0; j < classes[i].size; j++) {
                if (strcmp(classes[i].students[j].name, student_name) == 0) {
                    printf("Enter new scores:\n");
                    for (j = 0; j < MAX_SUBJECTS; j++) {
                        printf("Subject %d: ", j+1);
                        scanf("%d", &classes[i].students[j].score[j]);
                        classes[i].students[j].total += classes[i].students[j].score[j];
                    }
                    classes[i].students[j].average = (float) classes[i].students[j].total / MAX_SUBJECTS;
                    printf("Student modified.\n");
                    return;
                }
            }
            printf("Student not found.\n");
            return;
        }
    }
    printf("Class not found.\n");
}

void print_student_scores() {
    char class_name[MAX_NAME_LENGTH];
    int i, j;

    printf("Enter class name: ");
    scanf("%s", class_name);

    for (i = 0; i < num_classes; i++) {
        if (strcmp(classes[i].name, class_name) == 0) {
            for (j = 0; j < classes[i].size; j++) {
                printf("%s: ", classes[i].students[j].name);
                for (j = 0; j < MAX_SUBJECTS; j++) {
                    printf("%d ", classes[i].students[j].score[j]);
                }
                printf("Total: %d, Average: %.2f\n", classes[i].students[j].total, classes[i].students[j].average);
            }
            return;
        }
    }
    printf("Class not found.\n");
}

void print_student_list() {
    char class_name[MAX_NAME_LENGTH];
    int i, j;

    printf("Enter class name: ");
    scanf("%s", class_name);

    for (i = 0; i < num_classes; i++) {
        if (strcmp(classes[i].name, class_name) == 0) {
            printf("Student list:\n");
            for (j = 0; j < classes[i].size; j++) {
                printf("%s\n", classes[i].students[j].name);
            }
            return;
        }
    }
    printf("Class not found.\n");
}

void print_menu() {
    printf("1. Add class\n");
    printf("2. Add student\n");
    printf("3. Modify student\n");
    printf("4. Print student scores\n");
    printf("5. Print student list\n");
    printf("6. Quit\n");
}

int main() {
    int choice;

    do {
        print_menu();
        printf("Enter your choice: ");
        scanf("%d", &choice);

        switch (choice) {
            case 1:
                add_class();
                break;
            case 2:
                add_student();
                break;
            case 3:
                modify_student();
                break;
            case 4:
                print_student_scores();
                break;
            case 5:
                print_student_list();
                break;
            case 6:
                printf("Goodbye.\n");
                break;
            default:
                printf("Invalid choice.\n");
                break;
        }
    } while (choice != 6);

    return 0;
}

这段代码实现了一个简单的学生成绩管理系统，包括添加班级、添加学生、修改学生、打印学生成绩和打印学生名单等功能。你可以根据自己的需求对代码进行修改和扩展。