数据结构 — 静态链表

单链表的相对劣势

• 单链表的实现严重依赖指针
• 数据元素中必须包含一个额外的指针域
• 没有指针的程序设计语言无法实现

静态链表的定义

• 顺序表数组中的元素由两个数据域组成：data和next
• data域用于存储数据
• next域用于存储下一个元素在数组中的下标

静态链表是在顺序表的基础上利用数组实现的单链表

创建静态链表

获取第pos个元素操作

• 判断线性表是否合法
• 判断位置是否合法
• 由表头开始通过next域移动pos次后，当前元素的next域即要获取的元素在数组中的下标

插入元素到位置pos操作

• 判断线性表是否合法
• 判断插入位置是否合法
• 在数组中查找空闲位置index
• 由表头开始通过next域移动pos次后，当前元素的next域为要插入的位置
• 将新元素插入
• 线性表长度加一

删除第pos个元素操作

• 判断线性表是否合法
• 判断插入位置是否合法
• 获取第pos个元素
• 将第pos个元素从链表中删除
• 线性表长度减一

小结

• 静态链表其实是单链表的另外一种实现方式
• 静态链表的实现“媒介”不是指针而是数组
• 静态链表主要用于不支持指针的程序设计语言中
• 静态链表的实现是一种内存管理的简易方法

代码

StaticList.h

#ifndef _STATICLIST_H_
#define _STATICLIST_H_

typedef void StaticList;
typedef void StaticListNode;

StaticList* StaticList_Create(int capacity);

void StaticList_Destroy(StaticList* list);

void StaticList_Clear(StaticList* list);

int StaticList_Length(StaticList* list);

int StaticList_Capacity(StaticList* list);

int StaticList_Insert(StaticList* list, StaticListNode* node, int pos);

StaticListNode* StaticList_Get(StaticList* list, int pos);

StaticListNode* StaticList_Delete(StaticList* list, int pos);

#endif

StaticList.c

#include 
#include 
#include "StaticList.h"

#define AVAILABLE -1

typedef struct _tag_StaticListNode
{
    unsigned int data;
    int next;
} TStaticListNode;

typedef struct _tag_StaticList
{
    int capacity;
    TStaticListNode header;
    TStaticListNode node[];
} TStaticList;

StaticList* StaticList_Create(int capacity)
{
    TStaticList* ret = NULL;
    int i = 0;
    
    if( capacity >= 0 )
    {
        ret = (TStaticList*)malloc(sizeof(TStaticList) + sizeof(TStaticListNode) * (capacity + 1));
    }
    
    if( ret != NULL )
    {
        ret->capacity = capacity;
        ret->header.data = 0;
        ret->header.next = 0;
        
        for(i=1; i<=capacity; i++)
        {
            ret->node[i].next = AVAILABLE;
        }
    }
    
    return ret;
}

void StaticList_Destroy(StaticList* list)
{
    free(list);
}

void StaticList_Clear(StaticList* list)
{
    TStaticList* sList = (TStaticList*)list;
    int i = 0;
    
    if( sList != NULL )
    {
        sList->header.data = 0;
        sList->header.next = 0;
        
        for(i=1; i<=sList->capacity; i++)
        {
            sList->node[i].next = AVAILABLE;
        }
    }
}

int StaticList_Length(StaticList* list)
{
    TStaticList* sList = (TStaticList*)list;
    int ret = -1;
    
    if( sList != NULL )
    {
        ret = sList->header.data;
    }
    
    return ret;
}

int StaticList_Capacity(StaticList* list)
{
    TStaticList* sList = (TStaticList*)list;
    int ret = -1;
    
    if( sList != NULL )
    {
        ret = sList->capacity;
    }
    
    return ret;
}

int StaticList_Insert(StaticList* list, StaticListNode* node, int pos) 
{
    TStaticList* sList = (TStaticList*)list;
    int ret = (sList != NULL);
    int current = 0;
    int index = 0;
    int i = 0;
    
    ret = ret && (sList->header.data + 1 <= sList->capacity);
    ret = ret && (pos >=0) && (node != NULL);
    
    if( ret )
    {
        for(i=1; i<=sList->capacity; i++)
        {
            if( sList->node[i].next == AVAILABLE )
            {
                index = i;
                break;
            }
        }
        
        sList->node[index].data = (unsigned int)node;
        
        sList->node[0] = sList->header;
        
        for(i=0; (inode[current].next != 0); i++)
        {
            current = sList->node[current].next;
        }
        
        sList->node[index].next = sList->node[current].next;
        sList->node[current].next = index;
        
        sList->node[0].data++;
        
        sList->header = sList->node[0];
    }
    
    return ret;
}

StaticListNode* StaticList_Get(StaticList* list, int pos) 
{
    TStaticList* sList = (TStaticList*)list;
    StaticListNode* ret = NULL;
    int current = 0;
    int object = 0;
    int i = 0;
    
    if( (sList != NULL) && (0 <= pos) && (pos < sList->header.data) )
    {
        sList->node[0] = sList->header;
        
        for(i=0; inode[current].next;
        }
        
        object = sList->node[current].next;
        
        ret = (StaticListNode*)(sList->node[object].data);
    }
    
    return ret;
}

StaticListNode* StaticList_Delete(StaticList* list, int pos) 
{
    TStaticList* sList = (TStaticList*)list;
    StaticListNode* ret = NULL;
    int current = 0;
    int object = 0;
    int i = 0;
    
    if( (sList != NULL) && (0 <= pos) && (pos < sList->header.data) )
    {
        sList->node[0] = sList->header;
        
        for(i=0; inode[current].next;
        }
        
        object = sList->node[current].next;
        
        sList->node[current].next = sList->node[object].next;
        
        sList->node[0].data--;
        
        sList->header = sList->node[0];
        
        sList->node[object].next = AVAILABLE;
        
        ret = (StaticListNode*)(sList->node[object].data);
    }
    
    return ret;
}

main.c

#include 
#include 
#include "StaticList.h"

int main(int argc, char *argv[])
{
    StaticList* list = StaticList_Create(10);
    
    int index = 0;
    
    int i = 0;
    int j = 1;
    int k = 2;
    int x = 3;
    int y = 4;
    int z = 5;
    
    StaticList_Insert(list, &i, 0);
    StaticList_Insert(list, &j, 0);
    StaticList_Insert(list, &k, 0);
    
    for(index=0; index 0 )
    {
        int* p = (int*)StaticList_Delete(list, 0);
        
        printf("%d\n", *p);
    }
    
    printf("\n");
    
    StaticList_Insert(list, &x, 0);
    StaticList_Insert(list, &y, 0);
    StaticList_Insert(list, &z, 0);
    
    printf("Capacity: %d Length: %d\n", StaticList_Capacity(list), StaticList_Length(list));
    
    for(index=0; index