用c语言写一个学生管理系统

好的，下面是一个简单的学生管理系统的C语言代码：

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

#define MAX_STUDENT_NUM 100      // 最大学生数
#define MAX_NAME_LENGTH 20      // 姓名最大长度
#define MAX_COURSE_NUM 5        // 最大课程数

typedef struct Student {
    char name[MAX_NAME_LENGTH];
    int age;
    float scores[MAX_COURSE_NUM];
    float average_score;
} Student;

int student_num = 0;
Student student_list[MAX_STUDENT_NUM];

void add_student() {
    if (student_num >= MAX_STUDENT_NUM) {
        printf("学生数已满，无法添加新学生！\n");
        return;
    }

    Student new_student;
    printf("请输入学生姓名：");
    scanf("%s", new_student.name);
    printf("请输入学生年龄：");
    scanf("%d", &new_student.age);
    for (int i = 0; i < MAX_COURSE_NUM; i++) {
        printf("请输入第%d门课程成绩：", i + 1);
        scanf("%f", &new_student.scores[i]);
    }
    new_student.average_score = 0;
    for (int i = 0; i < MAX_COURSE_NUM; i++) {
        new_student.average_score += new_student.scores[i];
    }
    new_student.average_score /= MAX_COURSE_NUM;

    student_list[student_num++] = new_student;
    printf("添加学生成功！\n");
}

void show_all_students() {
    if (student_num == 0) {
        printf("没有学生记录！\n");
        return;
    }

    printf("| %-10s | %-5s |", "姓名", "年龄");
    for (int i = 0; i < MAX_COURSE_NUM; i++) {
        printf(" 第%d门课 ", i + 1);
    }
    printf("| 平均分 |\n");
    printf("+------------+-------+");
    for (int i = 0; i < MAX_COURSE_NUM; i++) {
        printf("+-------");
    }
    printf("+---------+\n");

    for (int i = 0; i < student_num; i++) {
        printf("| %-10s | %-5d |", student_list[i].name, student_list[i].age);
        for (int j = 0; j < MAX_COURSE_NUM; j++) {
            printf(" %-6.2f ", student_list[i].scores[j]);
        }
        printf("| %-7.2f |\n", student_list[i].average_score);
    }
}

void search_student() {
    char name[MAX_NAME_LENGTH];
    printf("请输入要查找的学生姓名：");
    scanf("%s", name);

    for (int i = 0; i < student_num; i++) {
        if (strcmp(student_list[i].name, name) == 0) {
            printf("| %-10s | %-5s |", "姓名", "年龄");
            for (int j = 0; j < MAX_COURSE_NUM; j++) {
                printf(" 第%d门课 ", j + 1);
            }
            printf("| 平均分 |\n");
            printf("+------------+-------+");
            for (int j = 0; j < MAX_COURSE_NUM; j++) {
                printf("+-------");
            }
            printf("+---------+\n");
            printf("| %-10s | %-5d |", student_list[i].name, student_list[i].age);
            for (int j = 0; j < MAX_COURSE_NUM; j++) {
                printf(" %-6.2f ", student_list[i].scores[j]);
            }
            printf("| %-7.2f |\n", student_list[i].average_score);
            return;
        }
    }

    printf("没有找到该学生记录！\n");
}

void menu() {
    printf("学生管理系统菜单：\n");
    printf("1. 添加学生\n");
    printf("2. 查看所有学生\n");
    printf("3. 查找学生\n");
    printf("4. 退出程序\n");
    printf("请选择操作：");
}

int main() {
    int choice;
    while (1) {
        menu();
        scanf("%d", &choice);
        switch (choice) {
            case 1:
                add_student();
                break;
            case 2:
                show_all_students();
                break;
            case 3:
                search_student();
                break;
            case 4:
                printf("程序已退出！\n");
                exit(0);
            default:
                printf("无效的选择！\n");
        }
    }
    return 0;
}

这个学生管理系统可以添加学生、查看所有学生、查找单个学生的记录。每个学生包含姓名、年龄、多门课程的成绩和平均分等信息。