栈

栈这种数据结构就太常见了

其特性也就是last in first out (lifo)，也就是因为它的这个特性，其是计算机的组成中的一个重要的数据结构

 栈有两种形式，顺序结构和链式结构

①顺序栈

#ifndef _SEQSTACK_H_
#define _SEQSTACK_H_

typedef void SeqStack;

SeqStack* SeqStack_Create(int capacity);

void SeqStack_Destroy(SeqStack* stack);

void SeqStack_Clear(SeqStack* stack);

int SeqStack_Push(SeqStack* stack, void* item);

void* SeqStack_Pop(SeqStack* stack);

void* SeqStack_Top(SeqStack* stack);

int SeqStack_Size(SeqStack* stack);

int SeqStack_Capacity(SeqStack* stack);

#endif

#include "SeqStack.h"
#include "SeqList.h"

SeqStack* SeqStack_Create(int capacity)
{
    return SeqList_Create(capacity);
}

void SeqStack_Destroy(SeqStack* stack)
{
    SeqList_Destroy(stack);
}

void SeqStack_Clear(SeqStack* stack)
{
    SeqList_Clear(stack);
}

int SeqStack_Push(SeqStack* stack, void* item)
{
    return SeqList_Insert(stack, item, SeqList_Length(stack));
}

void* SeqStack_Pop(SeqStack* stack)
{
    return SeqList_Delete(stack, SeqList_Length(stack) - 1);
}

void* SeqStack_Top(SeqStack* stack)
{
    return SeqList_Get(stack, SeqList_Length(stack) - 1);
}

int SeqStack_Size(SeqStack* stack)
{
    return SeqList_Length(stack);
}

int SeqStack_Capacity(SeqStack* stack)
{
    return SeqList_Capacity(stack);
}

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

/* run this program using the console pauser or add your own getch, system("pause") or input loop */

int main(int argc, char *argv[]) 
{
    SeqStack* stack = SeqStack_Create(20);
    int a[10];
    int i = 0;
    
    for(i=0; i<10; i++)
    {
        a[i] = i;
        
        SeqStack_Push(stack, a + i);
    }
    
    printf("Top: %d
", *(int*)SeqStack_Top(stack));
    printf("Capacity: %d
", SeqStack_Capacity(stack));
    printf("Length: %d
", SeqStack_Size(stack));
    
    while( SeqStack_Size(stack) > 0 )
    {
        printf("Pop: %d
", *(int*)SeqStack_Pop(stack));
    }
    
    SeqStack_Destroy(stack);
    
    return 0;
}

链式表

#ifndef _LINKSTACK_H_
#define _LINKSTACK_H_

typedef void LinkStack;

LinkStack* LinkStack_Create();

void LinkStack_Destroy(LinkStack* stack);

void LinkStack_Clear(LinkStack* stack);

int LinkStack_Push(LinkStack* stack, void* item);

void* LinkStack_Pop(LinkStack* stack);

void* LinkStack_Top(LinkStack* stack);

int LinkStack_Size(LinkStack* stack);

#endif

#include <malloc.h>
#include "LinkStack.h"
#include "LinkList.h"

typedef struct _tag_LinkStackNode
{
    LinkListNode header;
    void* item;
} TLinkStackNode;

LinkStack* LinkStack_Create()
{
    return LinkList_Create();
}

void LinkStack_Destroy(LinkStack* stack)
{
    LinkStack_Clear(stack);
    LinkList_Destroy(stack);
}

void LinkStack_Clear(LinkStack* stack)
{
    while( LinkStack_Size(stack) > 0 )
    {
        LinkStack_Pop(stack);
    }
}

int LinkStack_Push(LinkStack* stack, void* item)
{
    TLinkStackNode* node = (TLinkStackNode*)malloc(sizeof(TLinkStackNode));
    int ret = (node != NULL) && (item != NULL);
    
    if( ret )
    {
        node->item = item;
        
        ret  = LinkList_Insert(stack, (LinkListNode*)node, 0);
    }
    
    if( !ret )
    {
        free(node);
    }
    
    return ret;
}

void* LinkStack_Pop(LinkStack* stack)
{
    TLinkStackNode* node = (TLinkStackNode*)LinkList_Delete(stack, 0);
    void* ret = NULL;
    
    if( node != NULL )
    {
        ret = node->item;
        
        free(node);
    }
    
    return ret;
}

void* LinkStack_Top(LinkStack* stack)
{
    TLinkStackNode* node = (TLinkStackNode*)LinkList_Get(stack, 0);
    void* ret = NULL;
    
    if( node != NULL )
    {
        ret = node->item;
    }
    
    return ret;
}

int LinkStack_Size(LinkStack* stack)
{
    return LinkList_Length(stack);
}

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

/* run this program using the console pauser or add your own getch, system("pause") or input loop */

int main(int argc, char *argv[]) 
{
    LinkStack* stack = LinkStack_Create();
    int a[10];
    int i = 0;
    
    for(i=0; i<10; i++)
    {
        a[i] = i;
        
        LinkStack_Push(stack, a + i);
    }
    
    printf("Top: %d
", *(int*)LinkStack_Top(stack));
    printf("Length: %d
", LinkStack_Size(stack));
    
    while( LinkStack_Size(stack) > 0 )
    {
        printf("Pop: %d
", *(int*)LinkStack_Pop(stack));
    }
    
    LinkStack_Destroy(stack);
    
    return 0;
}

栈这种数据结构虽然简单，但是却用的很频繁