C/C++ 學習之路（第 10 課）：結構體鏈結串列實作學生成績管理系統

編輯：關於C語言

專案目標

運用結構體 + 鏈結串列實作動態學生資料管理：新增、查詢、修改、刪除。因學生人數不定，陣列固定大小不夠彈性，鏈結串列是經典解法。

資料結構定義

typedef struct Student {
    char no[4];       // 學號 (3 碼)
    char name[10];    // 姓名
    int chinese;      // 國文
    int math;         // 數學
    int english;      // 英文
    struct Student *next; // 指向下一筆
} StudentList;

核心功能模組

1. 初始化表頭 `init()`

void init(StudentList *&stuList) {
    stuList = (StudentList *)malloc(sizeof(StudentList));
    stuList->next = NULL; // 空串列
}

2. 新增資料 `insert()` — 尾插法

void insert(StudentList *&stuList) {
    StudentList *p = stuList, *s;
    while (p->next != NULL) p = p->next; // 找尾節點
    do {
        s = (StudentList *)malloc(sizeof(StudentList));
        puts("please insert student data(NO,Name,Chinese,Math,English):");
        scanf("%3s%10s", &s->no, &s->name);
        scanf("%d%d%d", &s->chinese, &s->math, &s->english);
        // 簡易驗證：分數 0-100
        if (s->chinese < 0 || s->chinese > 100 || ...) { puts("input data error !!!"); return; }
        s->next = NULL;
        p->next = s; p = p->next; // 掛上新節點，移動尾標
        fflush(stdin);
        puts("Continue? ENTER to yes or input no to exit");
    } while (getchar() == '\n');
}

3. 查詢顯示 `select()` — 遍歷列印

void select(StudentList *stuList) {
    StudentList *p = stuList->next;
    if (!p) { puts("there is no data,please insert!!"); getchar(); return; }
    puts("No\tName\tChinese\tMath\tEnglish");
    while (p) { printf("%s\t%s\t%d\t%d\t%d\n", p->no, p->name, p->chinese, p->math, p->english); p = p->next; }
    getchar();
}

4. 修改資料 `update()` — 依學號搜尋後覆寫

void update(StudentList *&stuList) {
    StudentList *p = stuList->next;
    char no[4]; gets(no);
    while (p && strcmp(p->no, no)) p = p->next; // 找節點
    if (!p) { puts("can't find this student's record!!!"); getchar(); return; }
    // 顯示舊資料後輸入新資料 (不含學號)
    puts("please update student data(Name,Chinese,Math,English):");
    scanf("%10s", &p->name); scanf("%d%d%d", &p->chinese, &p->math, &p->english);
    puts("update successful");
}

5. 刪除資料 `deleteData()` — 經典前驅節點法

void deleteData(StudentList *stuList) {
    StudentList *p = stuList, *q; // p 指向前驅
    char no[4]; gets(no);
    while (p->next && strcmp(p->next->no, no)) p = p->next;
    if (!p->next) { puts("can't find..."); getchar(); return; }
    puts("Are you sure delete? press ENTER to confirm");
    if (getchar() == '\n') {
        q = p->next; p->next = q->next; free(q); // 斷鏈 + 釋放
        puts("delete successful");
    }
    getchar();
}

主選單整合

void studentScoreManege() {
    StudentList *stuList = NULL; int oprate;
    init(stuList);
    do {
        system("cls"); // 清屏
        puts("1. select  2. insert  3. update  4. delete  0. exit");
        scanf("%d", &oprate);
        switch (oprate) {
            case 1: select(stuList); break;
            case 2: insert(stuList); break;
            case 3: update(stuList); break;
            case 4: deleteData(stuList); break;
        }
    } while (oprate != 0);
}