1、编写一个菜单驱动的学生成绩管理程序。实现如下管理功能： 能输入并显示 n 个学生的 m 门考试科目的成绩、总分和平均分。 按总分进行排序。 按学号进行排序。 任意输入一个学号，能显示该学生的姓名、各门功课的成绩。 将输入的学生成绩数据保存到文件中。 从文件中读出学生成绩数据。

好的，那么以下是一个简单的C语言代码示例，实现了您提出的这些功能：

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

#define MAX_NUM_STUDENTS 100
#define MAX_NAME_LENGTH 50
#define MAX_NUM_SUBJECTS 10

// 定义学生结构体
typedef struct {
    char name[MAX_NAME_LENGTH];
    int id;
    int scores[MAX_NUM_SUBJECTS];
    int total_score;
    float avg_score;
} Student;

// 定义全局变量
Student students[MAX_NUM_STUDENTS];
int num_students = 0;
int num_subjects = 0;

// 函数声明
void input_scores();
void sort_by_total_score();
void sort_by_id();
void display_student();
void save_scores();
void read_scores();

// 主函数
int main() {
    int choice;
    printf("Welcome to the Student Score Management System!\n");
    while (1) {
        printf("\nPlease select an option:\n");
        printf("1. Input scores\n");
        printf("2. Sort by total score\n");
        printf("3. Sort by student ID\n");
        printf("4. Display student information\n");
        printf("5. Save scores to file\n");
        printf("6. Read scores from file\n");
        printf("0. Exit\n");
        scanf("%d", &choice);
        switch (choice) {
            case 1: input_scores(); break;
            case 2: sort_by_total_score(); break;
            case 3: sort_by_id(); break;
            case 4: display_student(); break;
            case 5: save_scores(); break;
            case 6: read_scores(); break;
            case 0: exit(0);
            default: printf("Invalid choice! Please try again.\n");
        }
    }
    return 0;
}

// 输入学生成绩
void input_scores() {
    printf("Please enter the number of students: ");
    scanf("%d", &num_students);
    printf("Please enter the number of subjects: ");
    scanf("%d", &num_subjects);
    for (int i = 0; i < num_students; i++) {
        printf("Please enter the name of student %d: ", i + 1);
        scanf("%s", students[i].name);
        printf("Please enter the ID of student %d: ", i + 1);
        scanf("%d", &students[i].id);
        printf("Please enter the scores of student %d: ", i + 1);
        students[i].total_score = 0;
        for (int j = 0; j < num_subjects; j++) {
            scanf("%d", &students[i].scores[j]);
            students[i].total_score += students[i].scores[j];
        }
        students[i].avg_score = (float) students[i].total_score / num_subjects;
    }
    printf("Scores have been input.\n");
}

// 按总分排序
void sort_by_total_score() {
    for (int i = 0; i < num_students; i++) {
        for (int j = i + 1; j < num_students; j++) {
            if (students[i].total_score < students[j].total_score) {
                Student temp = students[i];
                students[i] = students[j];
                students[j] = temp;
            }
        }
    }
    printf("Scores have been sorted by total score.\n");
}

// 按学号排序
void sort_by_id() {
    for (int i = 0; i < num_students; i++) {
        for (int j = i + 1; j < num_students; j++) {
            if (students[i].id > students[j].id) {
                Student temp = students[i];
                students[i] = students[j];
                students[j] = temp;
            }
        }
    }
    printf("Scores have been sorted by student ID.\n");
}

// 显示学生信息
void display_student() {
    int id;
    printf("Please enter the student ID: ");
    scanf("%d", &id);
    int found = 0;
    for (int i = 0; i < num_students; i++) {
        if (students[i].id == id) {
            found = 1;
            printf("Name: %s\n", students[i].name);
            printf("Total score: %d\n", students[i].total_score);
            printf("Average score: %.2f\n", students[i].avg_score);
            printf("Scores for each subject:\n");
            for (int j = 0; j < num_subjects; j++) {
                printf("Subject %d: %d\n", j + 1, students[i].scores[j]);
            }
            break;
        }
    }
    if (!found) {
        printf("Student with ID %d not found.\n", id);
    }
}

// 将成绩数据保存到文件中
void save_scores() {
    FILE *fp;
    fp = fopen("scores.txt", "w");
    fprintf(fp, "%d %d\n", num_students, num_subjects);
    for (int i = 0; i < num_students; i++) {
        fprintf(fp, "%s %d ", students[i].name, students[i].id);
        for (int j = 0; j < num_subjects; j++) {
            fprintf(fp, "%d ", students[i].scores[j]);
        }
        fprintf(fp, "\n");
    }
    fclose(fp);
    printf("Scores have been saved to file.\n");
}

// 从文件中读出成绩数据
void read_scores() {
    FILE *fp;
    fp = fopen("scores.txt", "r");
    if (fp == NULL) {
        printf("File not found.\n");
        return;
    }
    fscanf(fp, "%d %d", &num_students, &num_subjects);
    for (int i = 0; i < num_students; i++) {
        fscanf(fp, "%s %d", students[i].name, &students[i].id);
        students[i].total_score = 0;
        for (int j = 0; j < num_subjects; j++) {
            fscanf(fp, "%d", &students[i].scores[j]);
            students[i].total_score += students[i].scores[j];
        }
        students[i].avg_score = (float) students[i].total_score / num_subjects;
    }
    fclose(fp);
    printf("Scores have been read from file.\n");
}

这个程序使用了结构体来存储每个学生的姓名、学号、成绩等信息，然后按照您的要求实现了各种功能，比如排序、查询、存储和读取数据等等。请注意，这只是一个简单的示例代码，您可以根据自己的需要进行适当的修改和优化。