串的堆分配存储表示的C语言实现

最新推荐文章于 2022-03-19 11:04:55 发布

原创最新推荐文章于 2022-03-19 11:04:55 发布 · 1.5k 阅读

4 ·

CC 4.0 BY-SA版权

文章标签：

#串

数据结构专栏收录该内容

50 篇文章

订阅专栏

本文详细介绍了串的堆分配及其相关操作的实现过程，包括字符串赋值、长度计算、比较、清除、拼接和子串提取。通过实例代码展示了如何在C语言环境下进行这些操作。

下面的代码实现了串的堆分配的大部分表示，只有clear清空串、截断字串没实现。代码如下：

#include 
#include 
#include 

#ifndef TRUE
#define TRUE 1
#endif
#ifndef FALSE
#define FALSE 0
#endif

typedef int Status;
typedef struct{
	char *ch;
	int	 length;
}HString;
HString T;
HString M;
HString S = {
	"fjds",
	4,
};

Status StrAssign(HString *T, char *chars);
int    StrLength(HString S);
int    StrCompare(HString S, HString T);
Status ClearString(HString *S);
Status Concat(HString *T, HString S1, HString S2);
Status SubString(HString S, int pos, int len);

Status StrAssign(HString *T, char *chars)
{
	int i, length;
	if(T->ch) free(T->ch);
	length = strlen(chars);
	if(length == 0){
		T->ch = NULL;
		T->length = 0;
		printf("the string length you give is zero.\n");
		return TRUE;	
	}
	T->ch = (char *)malloc(sizeof(char) * length);
	if(T->ch == NULL){
		printf("alloc memory for hstring failure.\n");	
		return FALSE;
	}
	T->ch = chars;
	T->length = length;
	return TRUE;	
}

int StrLength(HString S){
	return S.length;
}

int StrCompare(HString S, HString T)
{
	int i;
	for(i = 0; i < S.length && i < T.length; ++i){
		if(S.ch[i] != T.ch[i]) return S.ch[i] - T.ch[i];	
	}
	return S.length - T.length;
}

Status Concat(HString *T, HString S1, HString S2)
{
	int i;
	if(T->ch) free(T->ch);
	T->ch = (char *)malloc((S1.length + S2.length)*sizeof(char)); 
	if(T->ch == NULL)
		return FALSE;
	T->length = S1.length + S2.length;

	for(i = 0; i < S1.length; i++){
		T->ch[i] = S1.ch[i];	
	}
	for(i = 0; i < S2.length; i++){
		T->ch[S1.length+i] = S2.ch[i];	
	}

	return TRUE;
}

Status SubString(HString S, int pos, int len)
{
	if(pos < 1 || pos > S.length || len < 0 || len > S.length-pos+1) return FALSE;
	if(S.ch) free(S.ch);
	
	if(len == 0){
		S.ch = NULL; S.length = 0;
	}
}

int
main(void)
{
	int length;
	char *chars = "fjdskfjsl";
	if(StrAssign(&T, chars))
		printf("assign string success.\n");
	else
		printf("assign string failure.\n");
	
	printf("the string length is %d.\n", StrLength(T));

 	if(StrCompare(S, T) >= 0)
		printf("S is longer than T.\n");
	else
		printf("S is shorter than T.\n");

	if(Concat(&M, T, S) > 0)
		printf("concat success.\n");
	else
		printf("concat failure.\n");
	printf("M = %s.\n", M.ch);
}