用数组实现的单链表[C语言]

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

#define MAXSIZE 10  // 存储空间最大存储10个元素
#define SUCCESS 1
#define ERROR   0

typedef int ElementType;
typedef int Status;

typedef struct {
    ElementType data[MAXSIZE];
    int length;
} SqList;


/**
 * 初始化顺序存储的链表
 * 要想按引用传递指针的值，应该使用二级指针(也就是传递指针的地址)
 *
 * @param list  SqList**
 * @return  Status
 */
Status initSqList(SqList** list) {
    *list = (SqList*) malloc(sizeof(SqList));
    if (NULL == list) {
        return ERROR;
    }

    // 初始化链表中所有元素的值
    for (int i = 0; i < MAXSIZE; i++) {
        (*list)->data[i] = 0;
    }

    (*list)->length = 0;

    return SUCCESS;
}

/**
 * 向顺序存储的链表尾部插入元素
 *
 * @param list  SqList*
 * @param element   ElementType
 * @return  Status
 */
Status appendElement(SqList* list, ElementType element) {
    if (list->length >= MAXSIZE) {
        return ERROR;
    }

    list->data[list->length] = element;
    list->length++;

    return SUCCESS;
}

/**
 * 向顺序存储表中指定位置插入数据
 *
 * @param list  SqList*
 * @param pos   int
 * @param element   ElementType
 * @return  Status
 */
Status insertElement(SqList* list, int pos, ElementType element) {
    if (pos < 1 || list->length == MAXSIZE || pos > MAXSIZE) {
        return ERROR;
    }

    // 在length之前插入需要移动元素
    if (pos <= list->length) {
        for (int i = list->length-1; i >= pos; i--) {
            list->data[list->length] = list->data[list->length - 1];
        }
    }

    list->data[pos-1] = element;
    // 如果跳跃添加，length直接变成pos
    if (pos > list->length) {
        list->length = pos;
    } else {
        list->length++;
    }

    return SUCCESS;
}

/**
 * 删除顺序存储线性表最后一个元素
 *
 * @param list  SqList*
 * @param element   ElementType*
 * @return  Status
 */
Status popElement(SqList* list, ElementType* element) {
    if (list->length == 0) {
        return ERROR;
    }

    *element = list->data[list->length - 1];
    list->data[list->length - 1] = 0;
    list->length--;

    return SUCCESS;
}

/**
 * 删除顺序表中的元素
 *
 * @param list  SqList*
 * @param pos   int
 * @param element   ElementType*
 * @return  Status
 */
Status deleteElement(SqList* list, int pos, ElementType* element) {
    if (list->length == 0 || pos < 1 || pos > list->length) {
        return ERROR;
    }

    *element = list->data[pos - 1];

    // 移动元素
    for (int i = pos; i < list->length; i++) {
        list->data[pos - 1] = list->data[pos];
    }
    list->length--;

    return SUCCESS;
}

/**
 * 获取顺序存储表中指定位置的值
 * 链表是按引用传递,使用const约束不能修改链表的值
 *
 * @param list  SqList*
 * @param i int
 * @param element   ElementType
 * @return  Status
 */
Status getElement(const SqList* list, int i, ElementType* element) {
    if (list->length == 0 | i < 1 || i > MAXSIZE) {
        return ERROR;
    }

    *element = list->data[i - 1];

    return SUCCESS;
}

/**
 * 遍历顺序存储的链表
 *
 * @param list  SqList*
 * @return  Status
 */
Status traverseList(SqList *list) {
    if (list->length == 0) {
        return ERROR;
    }

    for (int i = 1; i <= list->length; i++) {
        ElementType element = list->data[i - 1];
        printf("%d\t", element);
    }
    printf("\n");

    return SUCCESS;
}

/**
 * 获取顺序存储表中指定位置的值
 * 链表是按值传递,传递的是链表的副本
 * (浪费内存空间，同样做到不能修改原链表的值)
 *
 * @param list  SqList*
 * @param i int
 * @param element   ElementType
 * @return  Status
 */
Status getElement2(SqList list, int i, ElementType* element) {
    if (list.length == 0 || i < 1 || i > list.length) {
        return ERROR;
    }

    *element = list.data[i - 1];

    return SUCCESS;
}

// 主函数测试用
int main() {

    SqList* list;
    int status = initSqList(&list);
    printf("链表中元素个数：%d\n", list->length);
    printf("初始化链表状态：%d\n", status);

    appendElement(list, 1);
    appendElement(list, 3);

    printf("链表中元素：");
    traverseList(list);

    insertElement(list, 4, 40);
    printf("链表中元素：");
    traverseList(list);

    ElementType element;
    getElement(list, 1, &element);
    printf("链表中第一个元素的值是：%d\n", element);

    getElement2(*list, 2, &element);
    printf("链表中第二个元素的值是：%d\n", element);

    status = getElement(list, 4, &element);
    if (status) {
        printf("链表中第四个元素的值是：%d\n", element);
    } else {
        printf("获取元素数据失败！");
    }

    status = getElement(list, 5, &element);
    if (status) {
        printf("链表中第五个元素的值是：%d\n", element);
    } else {
        printf("获取元素数据失败！");
    }

    printf("链表中元素个数:%d\n", list->length);
    printf("链表中元素：");
    traverseList(list);
    status = popElement(list, &element);
    if (status) {
        printf("删除的元素是：%d\n", element);
    } else {
        printf("删除失败！");
    }

    printf("链表中元素个数:%d\n", list->length);
    printf("链表中元素：");
    traverseList(list);
    status = deleteElement(list, 2, &element);
    if (status) {
        printf("删除的元素是：%d\n", element);
    } else {
        printf("删除失败！");
    }

    printf("链表中元素：");
    traverseList(list);

    return 0;
}