用c语言链表的方法完成学生管理系统，包括学生基本信息输入、输出、插入、删除、排序、查询、数据保存及打开

以下是一个简单的学生管理系统的代码，使用了链表来存储学生信息。具体功能包括学生基本信息输入、输出、插入、删除、排序、查询、数据保存及打开。

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

// 定义学生结构体
struct student {
    char name[50];
    int age;
    float score;
    struct student *next;
};

// 插入学生信息
void insert_student(struct student **head) {
    struct student *new_student = (struct student*)malloc(sizeof(struct 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);
    printf("请输入学生成绩：");
    scanf("%f", &new_student->score);
    new_student->next = NULL;
    if (*head == NULL) {
        *head = new_student;
    } else {
        struct student *p = *head;
        while (p->next != NULL) {
            p = p->next;
        }
        p->next = new_student;
    }
    printf("学生信息插入成功！\n\n");
}

// 输出学生信息
void print_student(struct student *head) {
    if (head == NULL) {
        printf("学生信息为空！\n\n");
    } else {
        printf("学生姓名\t学生年龄\t学生成绩\n");
        struct student *p = head;
        while (p != NULL) {
            printf("%s\t\t%d\t\t%.2f\n", p->name, p->age, p->score);
            p = p->next;
        }
        printf("\n");
    }
}

// 删除学生信息
void delete_student(struct student **head) {
    if (*head == NULL) {
        printf("学生信息为空！\n\n");
        return;
    }
    char name[50];
    printf("请输入要删除的学生姓名：");
    scanf("%s", name);
    struct student *p = *head;
    if (strcmp(p->name, name) == 0) {
        *head = p->next;
        free(p);
        printf("学生信息删除成功！\n\n");
        return;
    }
    while (p->next != NULL && strcmp(p->next->name, name) != 0) {
        p = p->next;
    }
    if (p->next == NULL) {
        printf("未找到该学生信息！\n\n");
        return;
    }
    struct student *del = p->next;
    p->next = del->next;
    free(del);
    printf("学生信息删除成功！\n\n");
}

// 排序学生信息
void sort_student(struct student **head) {
    if (*head == NULL) {
        printf("学生信息为空！\n\n");
        return;
    }
    struct student *p, *q, *tail = NULL;
    while (tail != (*head)->next) {
        p = *head;
        q = p->next;
        while (q != tail) {
            if (strcmp(p->name, q->name) > 0) {
                char name[50];
                strcpy(name, p->name);
                strcpy(p->name, q->name);
                strcpy(q->name, name);
                int age = p->age;
                p->age = q->age;
                q->age = age;
                float score = p->score;
                p->score = q->score;
                q->score = score;
            }
            p = p->next;
            q = q->next;
        }
        tail = p;
    }
    printf("学生信息排序成功！\n\n");
}

// 查询学生信息
void search_student(struct student *head) {
    if (head == NULL) {
        printf("学生信息为空！\n\n");
        return;
    }
    char name[50];
    printf("请输入要查询的学生姓名：");
    scanf("%s", name);
    struct student *p = head;
    while (p != NULL && strcmp(p->name, name) != 0) {
        p = p->next;
    }
    if (p == NULL) {
        printf("未找到该学生信息！\n\n");
    } else {
        printf("学生姓名\t学生年龄\t学生成绩\n");
        printf("%s\t\t%d\t\t%.2f\n\n", p->name, p->age, p->score);
    }
}

// 保存学生信息到文件
void save_student(struct student *head) {
    if (head == NULL) {
        printf("学生信息为空！\n\n");
        return;
    }
    FILE *fp = fopen("student.txt", "w");
    if (fp == NULL) {
        printf("文件保存失败！\n\n");
        return;
    }
    struct student *p = head;
    while (p != NULL) {
        fprintf(fp, "%s %d %.2f\n", p->name, p->age, p->score);
        p = p->next;
    }
    fclose(fp);
    printf("学生信息保存成功！\n\n");
}

// 打开文件中的学生信息
void open_student(struct student **head) {
    FILE *fp = fopen("student.txt", "r");
    if (fp == NULL) {
        printf("文件打开失败！\n\n");
        return;
    }
    char name[50];
    int age;
    float score;
    while (fscanf(fp, "%s %d %f\n", name, &age, &score) != EOF) {
        struct student *new_student = (struct student*)malloc(sizeof(struct student));
        strcpy(new_student->name, name);
        new_student->age = age;
        new_student->score = score;
        new_student->next = NULL;
        if (*head == NULL) {
            *head = new_student;
        } else {
            struct student *p = *head;
            while (p->next != NULL) {
                p = p->next;
            }
            p->next = new_student;
        }
    }
    fclose(fp);
    printf("学生信息打开成功！\n\n");
}

int main() {
    struct student *head = NULL;
    int choice;
    while (1) {
        printf("请选择操作：\n");
        printf("1. 插入学生信息\n");
        printf("2. 输出学生信息\n");
        printf("3. 删除学生信息\n");
        printf("4. 排序学生信息\n");
        printf("5. 查询学生信息\n");
        printf("6. 保存学生信息到文件\n");
        printf("7. 打开文件中的学生信息\n");
        printf("0. 退出程序\n");
        printf("请输入操作编号：");
        scanf("%d", &choice);
        printf("\n");
        switch (choice) {
            case 1:
                insert_student(&head);
                break;
            case 2:
                print_student(head);
                break;
            case 3:
                delete_student(&head);
                break;
            case 4:
                sort_student(&head);
                break;
            case 5:
                search_student(head);
                break;
            case 6:
                save_student(head);
                break;
            case 7:
                open_student(&head);
                break;
            case 0:
                printf("程序已退出！\n");
                exit(0);
            default:
                printf("输入的操作编号有误！\n\n");
                break;
        }
    }
    return 0;
}

注意：该代码只是一个简单的示例，实际应用中可能需要更多的功能和异常处理。