单链表操作模拟系统(12种功能)

    今晚花了一晚上写了一个功能较完善的单链表操作模拟系统, 有助于帮助初学者初始单链表的各种操作. 虽然系统已经过本人简单的测试, 但可能还存在bug, 还请各位朋友帮我一起测试这个系统, 如有问题直接在评论区留言即可, 谢谢大家!

#include<stdio.h>
#include<stdlib.h>
short InitLinkList(struct Node* &, struct Node* &);
short RearInsert(struct Node* &, short);
short IsEmpty(struct Node* &);
void Traversal(struct Node* &);
short GetListLength(struct Node* &);
short GetListLength2(struct Node* &);
short HeadInsert(struct Node* &, struct Node* &, short);
short GetElemPosition(struct Node* &, short);
short DeleteNodeByValue(struct Node* &, struct Node* &, short);
short DeleteNodeByPos(struct Node* &, struct Node* & ,short);
/* 单链表结点的定义 */
struct Node
{
    short data;
    struct Node* next;
};
int main()
{
    /* 单链表的头指针 */
    struct Node *head;
    /* 单链表的尾指针 */
    struct Node *rear;
    /* 操作代码 */
    short choice;
    short temp;
    short pos;
    short length;
    /* 头结点初始化标志 */
    short headInit = 0;
    printf("-------------------------单链表操作模拟系统---------------------------\n");
    printf("--------------------------1. 初始化头结点-----------------------------\n");
    printf("--------------------------2. 插入新结点(头插法)-----------------------\n");
    printf("--------------------------3. 插入新结点(尾插法)-----------------------\n");
    printf("--------------------------4. 按位置删除结点---------------------------\n");
    printf("--------------------------5. 按数值删除结点---------------------------\n");
    printf("--------------------------6. 获取当前表长-----------------------------\n");
    printf("--------------------------7. 遍历单链表-------------------------------\n");
    printf("--------------------------8. 判断是否为空表---------------------------\n");
    printf("--------------------------9. 根据数值查找结点位置---------------------\n");
    printf("-------------------------10. 退出系统---------------------------------\n");
    printf("-------------------------11. 清空单链表-------------------------------\n");
    printf("-------------------------12. 销毁单链表-------------------------------\n");
    /* */
    while(1)
    {
        printf("请输入操作码(1~12): ");
        while(scanf("%hd", &choice) != 1 || choice < 1 || choice > 12)
        {
            printf("请输入合法操作码.\n");
            while(getchar() != '\n') ;
            printf("请输入操作码(1~12): ");
        }
        if(choice == 10)
        {
            printf("欢迎再次使用, 再见!\n");
            break;
        }
        if(headInit == 1 && choice == 1)
        {
            /* 企图重复初始化头结点 */
            /* 拦截该行为 */
            printf("请不要重复初始化头结点.\n");
            continue;
        }
        else if(headInit == 0 && choice == 12)
        {
            /* 企图重复销毁链表 */
            /* 拦截该行为 */
            printf("请先初始化头结点再尝试销毁单链表.\n");
            continue;
        }
        else if(headInit == 0 && choice != 1)
        {
            /* 企图不初始化头结点就开始访问链表 */
            /* 拦截该行为 */
            printf("请先初始化头结点再对单链表进行操作.\n");
            continue;
        }
        switch(choice)
        {
            case 1:
                if(InitLinkList(head, rear) == -1)
                {
                    /* 头结点申请失败 */
                    printf("头结点申请失败, 程序结束.\n");
                    exit(0);
                }
                printf("头结点初始化成功.\n");
                headInit = 1;
                break;
            case 2:
                printf("请输入要插入结点的数据域: ");
                while(scanf("%hd", &temp) != 1)
                {
                    while(getchar() != '\n') ;
                    printf("请输入合法数据.\n");
                    printf("请输入要插入结点的数据域: ");
                }
                if(HeadInsert(head, rear, temp) == -1)
                {
                    /* 新结点申请失败 */
                    printf("结点申请失败.\n");
                }
                else
                {
                    /* 结点插入成功 */
                    printf("数据域为%3hd的结点插入成功.\n", temp);
                }
                break;
            case 3:
                printf("请输入要插入结点的数据域: ");
                while(scanf("%hd", &temp) != 1)
                {
                    while(getchar() != '\n') ;
                    printf("请输入合法数据.\n");
                    printf("请输入要插入结点的数据域: ");
                }
                if(RearInsert(rear, temp) == -1)
                {
                    /* 新结点申请失败 */
                    printf("结点申请失败.\n");
                }
                else
                {
                    /* 结点插入成功 */
                    printf("数据域为%3hd的结点插入成功.\n", temp);
                }
                break;
            case 4:
                printf("请输入要删除结点的下标: ");
                while(scanf("%hd", &temp) != 1 || temp < 1)
                {
                    while(getchar() != '\n') ;
                    printf("请输入合法数据.\n");
                    printf("请输入要删除结点的下标: ");
                }
                if(DeleteNodeByPos(head, rear, temp) == -1)
                {
                    /* 给定位置超出表长范围 */
                    printf("给定位置超出表长范围.\n");
                    printf("删除失败.\n");
                }
                else
                {
                    /* 结点删除成功 */
                    printf("数据域为%3hd的结点删除成功.\n", temp);
                }
                break;
            case 5:
                printf("请输入要删除结点数据域的值: ");
                while(scanf("%hd", &temp) != 1)
                {
                    while(getchar() != '\n') ;
                    printf("请输入合法数据.\n");
                    printf("请输入要删除结点数据域的值: ");
                }
                if(DeleteNodeByValue(head, rear, temp) == -1)
                {
                    /* 未找到相应结点 */
                    printf("未找到数据域为%3hd的结点.\n", temp);
                    printf("删除失败.\n");
                }
                else
                {
                    /* 结点删除成功 */
                    printf("数据域为%3hd的结点已删除.\n", temp);
                }
                break;
            case 6:
                printf("当前表长为%3hd.\n", GetListLength(head));
                break;
            case 7:
                printf("当前表中元素为: ");
                Traversal(head);
                break;
            case 8:
                if(IsEmpty(head) == 1)
                {
                    printf("当前单链表为空表.\n");
                }
                else
                {
                    printf("当前单链表为非空表.\n");
                }
                break;
            case 9:
                printf("请输入要查找结点的数据域: ");
                while(scanf("%hd", &temp) != 1)
                {
                    while(getchar() != '\n') ;
                    printf("请输入合法数据.\n");
                    printf("请输入要查找结点的数据域: ");
                }
                pos = GetElemPosition(head, temp);
                if(pos == -1)
                {
                    /* 未找到该结点 */
                    printf("数据域为%3hd的结点不在表中.\n", temp);
                }
                else
                {
                    printf("数据域为%3hd的结点在表中的下标为%3hd.\n", temp, pos);
                }
                break;
            case 11:
                if(IsEmpty(head) == 1)
                {
                    /* 表空 */
                    printf("表已空, 不必重复清空.\n");
                }
                else
                {
                    /* 表不空 */
                    /* 获取表长 */
                    length = GetListLength(head);
                    short i = 0;
                    /* 执行length次循环, 每次都将下标为1的结点删除, length次后表空 */
                    while(i < length)
                    {
                        DeleteNodeByPos(head, rear, 1);
                        i ++;
                    }
                    printf("已清空单链表.\n");
                }
                break;
            case 12:
                /* 进入循环后的判断语句确保当前链表未被销毁, 即头结点存在 */
                /* 先清空链表数据结点 */
                if(IsEmpty(head) == 1)
                {
                    /* 已是空表, 只需要销毁头结点即可 */
                    free(head);
                    headInit = 0;
                }
                else
                {
                    /* 表中还有数据结点, 应先销毁数据结点 */
                    length = GetListLength(head);
                    short j = 0;
                    while(j < length)
                    {
                        DeleteNodeByPos(head, rear, 1);
                        j ++;
                    }
                    /* 接着销毁头结点 */
                    free(head);
                    headInit = 0;
                }
                printf("单链表已销毁.\n");
                break;
        }
    }
}
/* 根据给定位置删除表中元素 */
short DeleteNodeByPos(struct Node* &head, struct Node* &rear, short pos)
{
    short length = GetListLength(head);
    if(pos > length || pos < 1)
    {
        /* 给定位置已超出表长范围 */
        return -1;
    }
    short i = 1;
    struct Node *p = head -> next;
    struct Node *q = head;
    while(p != NULL)
    {
        if(i == pos)
        {
            /* 定位到删除位置 */
            if(p -> next == NULL)
            {
                /* 待删除结点为表尾结点 */
                /* 需要修改尾指针rear */
                rear = q;
            }
            q -> next = p -> next;
            free(p);
            return 1;
        }
        i ++;
        p = p -> next;
        q = q -> next;
    }
}
/* 删除表中第一个值为value的元素 */
short DeleteNodeByValue(struct Node* &head, struct Node* &rear, short value)
{
    struct Node *p = head -> next;
    struct Node *q = head;
    while(p != NULL)
    {
        if(p -> data == value)
        {
            /* 找到待删除结点 */
            if(p -> next == NULL)
            {
                /* 待删除结点为表尾结点 */
                /* 此时需要修改尾指针rear */
                rear = q;
            }
            q -> next = p -> next;
            free(p);
            return 1;
        }
        p = p -> next;
        q = q -> next;
    }
    /* 未找到值为value的元素 */
    return -1;
}
/* 查找数据元素value是否在表中, 如果在, 返回该结点在表中的位置 */
short GetElemPosition(struct Node* &head, short value)
{
    short i = 1;
    struct Node *p = head -> next;
    while(p != NULL)
    {
        if(p -> data == value)
        {
            return i;
        }
        p = p -> next;
        i ++;
    }
    /* 未找到数据元素value */
    return -1;
}
/* 单链表的头插法 */
short HeadInsert(struct Node* &head, struct Node* &rear, short value)
{
    struct Node *p = head -> next;
    struct Node *N = (struct Node*)malloc(sizeof(struct Node));
    if(N != NULL)
    {
        /* 结点申请成功 */
        if(IsEmpty(head) == 1)
        {
            /* 表空, 此时需要修改尾指针 */
            rear = N;
        }
        N -> next = p;
        head -> next = N;
        N -> data = value;
        return 1;
    }
    else
    {
        /* 结点申请失败 */
        return -1;
    }
}
/* 获取当前表长 */
short GetListLength2(struct Node* &head)
{
    short length = 0;
    struct Node *p = head -> next;
    while(p != NULL)
    {
        length ++;
        p = p -> next;
    }
    return length;
}
/* 获取当前表长 */
short GetListLength(struct Node* &head)
{
    short length = 0;
    struct Node *p = head;
    while(p -> next != NULL)
    {
        length ++;
        p = p -> next;
    }
    return length;
}
/* 遍历单链表并输出 */
void Traversal(struct Node* &head)
{
    if(IsEmpty(head) == 0)
    {
        /* 表非空 */
        struct Node *p = head -> next;
        while(p != NULL)
        {
            printf("%3hd", p -> data);
            p = p -> next;
        }
    }
    putchar('\n');
}
/* 判断单链表是否为空表 */
short IsEmpty(struct Node* &head)
{
    if(head -> next == NULL)
    {
        /* 表空 */
        return 1;
    }
    else
    {
        /* 表非空 */
        return 0;
    }
}
/* 单链表的尾插法 */
short RearInsert(struct Node* &rear, short value)
{
    struct Node *p = (struct Node*)malloc(sizeof(struct Node));
    if(p != NULL)
    {
        /* 结点空间申请成功 */
        p -> data = value;
        rear -> next = p;
        p -> next = NULL;
        rear = p;
        return 1;
    }
    else
    {
        /* 结点空间申请失败 */
        return -1;
    }
}
/* 创建头结点 */
short InitLinkList(struct Node* &head, struct Node* &rear)
{
    head = (struct Node*)malloc(sizeof(struct Node));
    if(head != NULL)
    {
        /* 头结点申请成功 */
        printf("头结点申请成功.\n");
        head -> data = 0;
        head -> next = NULL;
        rear = head;
        return 1;
    }
    else
    {
        printf("头结点申请失败.\n");
        return -1;
    }
}