实现一个完整的c语言学生信息管理系统

好的，这里是一个简单的C语言学生信息管理系统的实现，供您参考：

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

#define NAME_LEN 20
#define NUM_LEN 10
#define MAX_STUDENT 100

typedef struct {
    char name[NAME_LEN];
    char num[NUM_LEN];
    int age;
    float score;
} Student;

void add_student(Student students[], int *count);
void delete_student(Student students[], int *count);
void modify_student(Student students[], int count);
void search_student(Student students[], int count);
void show_all_student(Student students[], int count);

int main() {
    Student students[MAX_STUDENT];
    int count = 0;
    int choice;
    
    while (1) {
        printf("1. 添加学生信息\n");
        printf("2. 删除学生信息\n");
        printf("3. 修改学生信息\n");
        printf("4. 查找学生信息\n");
        printf("5. 显示所有学生信息\n");
        printf("6. 退出程序\n");
        printf("请选择操作：\n");
        scanf("%d", &choice);
        
        switch (choice) {
            case 1:
                add_student(students, &count);
                break;
            case 2:
                delete_student(students, &count);
                break;
            case 3:
                modify_student(students, count);
                break;
            case 4:
                search_student(students, count);
                break;
            case 5:
                show_all_student(students, count);
                break;
            case 6:
                exit(0);
            default:
                printf("输入有误，请重新输入！\n");
                break;
        }
    }
    return 0;
}

void add_student(Student students[], int *count) {
    if (*count >= MAX_STUDENT) {
        printf("学生信息已满，无法添加！\n");
        return;
    }
    printf("请输入学生信息：\n");
    printf("姓名：");
    scanf("%s", students[*count].name);
    printf("学号：");
    scanf("%s", students[*count].num);
    printf("年龄：");
    scanf("%d", &students[*count].age);
    printf("成绩：");
    scanf("%f", &students[*count].score);
    printf("添加成功！\n");
    (*count)++;
}

void delete_student(Student students[], int *count) {
    char num[NUM_LEN];
    int i, j;
    printf("请输入要删除的学生学号：");
    scanf("%s", num);
    for (i = 0; i < *count; i++) {
        if (strcmp(num, students[i].num) == 0) {
            for (j = i; j < *count - 1; j++) {
                students[j] = students[j + 1];
            }
            (*count)--;
            printf("删除成功！\n");
            return;
        }
    }
    printf("未找到该学生信息！\n");
}

void modify_student(Student students[], int count) {
    char num[NUM_LEN];
    int i;
    printf("请输入要修改的学生学号：");
    scanf("%s", num);
    for (i = 0; i < count; i++) {
        if (strcmp(num, students[i].num) == 0) {
            printf("请输入修改后的信息：\n");
            printf("姓名：");
            scanf("%s", students[i].name);
            printf("年龄：");
            scanf("%d", &students[i].age);
            printf("成绩：");
            scanf("%f", &students[i].score);
            printf("修改成功！\n");
            return;
        }
    }
    printf("未找到该学生信息！\n");
}

void search_student(Student students[], int count) {
    char num[NUM_LEN];
    int i;
    printf("请输入要查找的学生学号：");
    scanf("%s", num);
    for (i = 0; i < count; i++) {
        if (strcmp(num, students[i].num) == 0) {
            printf("学生信息如下：\n");
            printf("姓名：%s\n", students[i].name);
            printf("学号：%s\n", students[i].num);
            printf("年龄：%d\n", students[i].age);
            printf("成绩：%.2f\n", students[i].score);
            return;
        }
    }
    printf("未找到该学生信息！\n");
}

void show_all_student(Student students[], int count) {
    int i;
    printf("所有学生信息如下：\n");
    for (i = 0; i < count; i++) {
        printf("姓名：%s\n", students[i].name);
        printf("学号：%s\n", students[i].num);
        printf("年龄：%d\n", students[i].age);
        printf("成绩：%.2f\n", students[i].score);
    }
}

这个学生信息管理系统实现了添加、删除、修改、查找、显示所有学生信息等功能，使用了结构体存储学生信息，可以存放最多100个学生信息。您可以根据自己的需求进行修改和优化。