C语言中动态数组的构造实例

最新推荐文章于 2024-02-02 19:48:42 发布

最新推荐文章于 2024-02-02 19:48:42 发布 · 95 阅读

文章标签：

#c/c++ #数据结构与算法 #java

本文介绍了一种在C语言中实现动态数组的方法，类似于高级语言中的Vector或ArrayList。通过定义宏和结构体来创建可以自动扩展容量的数组，并提供了初始化、增加元素、删除元素等操作。

进行C语言的编程时，大家经常要用到类似JAVA, .NET高级语言中的Vector或ArrayList之类的数据结构，这里提供一则实例告诉大家如何生成这样的数据结构。

#ifndef __DN_DA__
#define __DN_DA__

#include <tchar.h>
#include <assert.h>

#define DN_DYNAMIC_ARRAY(ITEM, ARRAY_NAME)/
typedef struct _##ARRAY_NAME{/
unsigned int count;/
unsigned int capacity;/
ITEM **array;/
} ARRAY_NAME

DN_DYNAMIC_ARRAY(void, DS_VOID_ARRAY);

DN_DYNAMIC_ARRAY(TCHAR, STRING_ARRAY);

void *dynamicNewItem(DS_VOID_ARRAY *pArray, UINT nItemSize);
void dynamicDeleteItem(DS_VOID_ARRAY *pArray, UINT index);
BOOL dynamicDeleteItemByValue(DS_VOID_ARRAY *pArray, PVOID pItem);
BOOL dynamicDeleteStringByValue(DS_VOID_ARRAY *pArray, LPCTSTR pItem);
void dynamicFreeItems(DS_VOID_ARRAY *pArray);

__inline void dynamicInitStrings(STRING_ARRAY *pStrings)
{
pStrings->count = 0;
pStrings->capacity = 0;
pStrings->array = NULL;
}

__inline TCHAR* dynamicNewString(STRING_ARRAY *pStrings, UINT len)
{
return (TCHAR *)dynamicNewItem((DS_VOID_ARRAY*)pStrings, sizeof(TCHAR) * len);
}

__inline TCHAR* dynamicDupString(STRING_ARRAY *pStrings, const TCHAR *psz)
{
TCHAR* p = (TCHAR *)dynamicNewItem((DS_VOID_ARRAY*)pStrings, sizeof(TCHAR) * ((unsigned)_tcslen(psz) + 1));

if(p != NULL){
_tcscpy(p, psz);
}

return p;
}

__inline void dynamicDestroyStrings(STRING_ARRAY *pStrings)
{
dynamicFreeItems((DS_VOID_ARRAY*)pStrings);
}

#define DARRAY_INIT_SIZE4
#define DARRAY_EXPANDED_SIZE4

__inline void *dynamicNewItem(DS_VOID_ARRAY *pArray, UINT nItemSize)
{
void *pItem;

assert(pArray != NULL);

if(pArray->capacity == 0){
pArray->array = (void **)malloc(sizeof(void*) * DARRAY_INIT_SIZE);//allocate the slot

if(pArray->array == NULL){
return NULL;
}
else{
pArray->capacity = DARRAY_INIT_SIZE;
}
}

if(pArray->capacity == pArray->count ){//capacity == count, we need expand the slot
void *p = realloc(pArray->array, sizeof(void*) * (pArray->capacity + DARRAY_EXPANDED_SIZE));

if(p == NULL){
return NULL;
}

pArray->array = (void**)p;
pArray->capacity = pArray->capacity + DARRAY_EXPANDED_SIZE;
}

pItem = malloc(nItemSize);

if(pItem == NULL){
return NULL;
}

memset(pItem, 0, nItemSize);

pArray->array[pArray->count ++] = pItem;

return pItem;
}

__inline void dynamicDeleteItem(DS_VOID_ARRAY *pArray, UINT index)
{
UINT i;

assert(pArray != NULL);

assert(index >= 0 && index < pArray->count);

free(pArray->array[index]);

for( i = index; i < pArray->count - 1; i ++){
pArray->array[ i ] = pArray->array[i + 1];
}

pArray->array[pArray->count - 1] = NULL;

pArray->count --;
}

__inline BOOL dynamicDeleteItemByValue(DS_VOID_ARRAY *pArray, PVOID pItem)
{
UINT i;

assert(pArray != NULL);

for( i = 0; i < pArray->count; i ++){
if(pArray->array[i] == pItem){
dynamicDeleteItem(pArray, i);
return TRUE;
}
}

return FALSE;
}

__inline BOOL dynamicDeleteStringByValue(DS_VOID_ARRAY *pArray, LPCTSTR pItem)
{
UINT i;

assert(pArray != NULL);

for( i = 0; i < pArray->count; i ++){
if( _tcscmp((LPTSTR)(pArray->array[i]), pItem) == 0 ){
dynamicDeleteItem(pArray, i);
return TRUE;
}
}

return FALSE;
}

__inline void dynamicFreeItems(DS_VOID_ARRAY *pArray)
{
UINT i;

assert(pArray != NULL);

for( i = 0; i < pArray->count; i ++){
assert(pArray->array[i] != NULL);
free(pArray->array[i]);
}

if((void*)pArray->array != NULL){
free((void*)pArray->array);
}

pArray->capacity= 0;
pArray->count= 0;
pArray->array= (void **)NULL;
}

#endif