用c语言写一个学生成绩管理系统

好的，下面是一个简单的学生成绩管理系统的 C 语言代码实现，包括添加学生信息、查询学生信息、修改学生信息、删除学生信息、计算总分和平均分等功能。

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

#define MAX_STUDENT_NUM 100    // 学生数量上限
#define NAME_LENGTH 20         // 姓名长度上限

// 学生信息结构体
struct Student {
    char name[NAME_LENGTH];   // 姓名
    int math_score;           // 数学成绩
    int english_score;        // 英语成绩
    int computer_score;       // 计算机成绩
    int total_score;          // 总分
    float avg_score;          // 平均分
};

// 学生信息数组
struct Student students[MAX_STUDENT_NUM];
int student_num = 0;          // 当前学生数量

// 添加学生信息
void add_student() {
    if (student_num >= MAX_STUDENT_NUM) {
        printf("学生数量已达到上限，无法添加新学生！\n");
        return;
    }

    char name[NAME_LENGTH];
    int math_score, english_score, computer_score;

    printf("请输入学生姓名：");
    scanf("%s", name);
    printf("请输入数学成绩：");
    scanf("%d", &math_score);
    printf("请输入英语成绩：");
    scanf("%d", &english_score);
    printf("请输入计算机成绩：");
    scanf("%d", &computer_score);

    struct Student student;
    strcpy(student.name, name);
    student.math_score = math_score;
    student.english_score = english_score;
    student.computer_score = computer_score;
    student.total_score = math_score + english_score + computer_score;
    student.avg_score = (float)student.total_score / 3;

    students[student_num++] = student;

    printf("学生信息添加成功！\n");
}

// 查询学生信息
void query_student() {
    if (student_num == 0) {
        printf("当前没有学生信息！\n");
        return;
    }

    char name[NAME_LENGTH];

    printf("请输入要查询的学生姓名：");
    scanf("%s", name);

    int found = 0;
    for (int i = 0; i < student_num; i++) {
        if (strcmp(students[i].name, name) == 0) {
            printf("姓名：%s\n", students[i].name);
            printf("数学成绩：%d\n", students[i].math_score);
            printf("英语成绩：%d\n", students[i].english_score);
            printf("计算机成绩：%d\n", students[i].computer_score);
            printf("总分：%d\n", students[i].total_score);
            printf("平均分：%.2f\n", students[i].avg_score);
            found = 1;
            break;
        }
    }

    if (!found) {
        printf("找不到该学生的信息！\n");
    }
}

// 修改学生信息
void modify_student() {
    if (student_num == 0) {
        printf("当前没有学生信息！\n");
        return;
    }

    char name[NAME_LENGTH];

    printf("请输入要修改的学生姓名：");
    scanf("%s", name);

    int found = 0;
    for (int i = 0; i < student_num; i++) {
        if (strcmp(students[i].name, name) == 0) {
            printf("请输入新的数学成绩：");
            scanf("%d", &students[i].math_score);
            printf("请输入新的英语成绩：");
            scanf("%d", &students[i].english_score);
            printf("请输入新的计算机成绩：");
            scanf("%d", &students[i].computer_score);

            students[i].total_score = students[i].math_score + students[i].english_score + students[i].computer_score;
            students[i].avg_score = (float)students[i].total_score / 3;

            printf("学生信息修改成功！\n");
            found = 1;
            break;
        }
    }

    if (!found) {
        printf("找不到该学生的信息！\n");
    }
}

// 删除学生信息
void delete_student() {
    if (student_num == 0) {
        printf("当前没有学生信息！\n");
        return;
    }

    char name[NAME_LENGTH];

    printf("请输入要删除的学生姓名：");
    scanf("%s", name);

    int found = 0;
    for (int i = 0; i < student_num; i++) {
        if (strcmp(students[i].name, name) == 0) {
            for (int j = i; j < student_num - 1; j++) {
                students[j] = students[j + 1];
            }
            student_num--;
            printf("学生信息删除成功！\n");
            found = 1;
            break;
        }
    }

    if (!found) {
        printf("找不到该学生的信息！\n");
    }
}

// 计算总分和平均分
void compute_score() {
    if (student_num == 0) {
        printf("当前没有学生信息！\n");
        return;
    }

    int total_score = 0;
    for (int i = 0; i < student_num; i++) {
        total_score += students[i].total_score;
    }
    float avg_score = (float)total_score / student_num;

    printf("学生总分：%d\n", total_score);
    printf("学生平均分：%.2f\n", avg_score);
}

int main() {
    int choice;

    while (1) {
        printf("请选择要执行的操作：\n");
        printf("1. 添加学生信息\n");
        printf("2. 查询学生信息\n");
        printf("3. 修改学生信息\n");
        printf("4. 删除学生信息\n");
        printf("5. 计算总分和平均分\n");
        printf("6. 退出程序\n");

        printf("请输入要执行的操作编号：");
        scanf("%d", &choice);

        switch (choice) {
        case 1:
            add_student();
            break;
        case 2:
            query_student();
            break;
        case 3:
            modify_student();
            break;
        case 4:
            delete_student();
            break;
        case 5:
            compute_score();
            break;
        case 6:
            printf("程序已退出！\n");
            exit(0);
        default:
            printf("无效操作，请重新输入！\n");
            break;
        }
    }

    return 0;
}

这个学生成绩管理系统可以通过菜单选择实现不同的操作，包括添加学生信息、查询学生信息、修改学生信息、删除学生信息、计算总分和平均分等功能。你可以根据自己的需要进行修改和完善。