数据结构字符串动态堆存储实现

如题；这是一套完整的可运行的代码；需要读者有一定的基础去阅读；

语言是用C语言实现；在C++环境中编写；在C++中可直接运行；在C语言中需要改部分头文件和输出语句；

头文件；这要是代码的声明部分；

# ifndef _HEAPSTRING_
# define _HEAPSTRING_

# include <iostream>
using namespace std;

typedef struct
{
	char * str;
	int len;
}HeapStirng, * PHeapString;

PHeapString InitString(void);
void ClearString(PHeapString H);
void DestroyString(PHeapString * pH);

int LengthString(PHeapString H);
bool EmptyString(PHeapString H);

bool AssignString(PHeapString H, const char * const p);
bool CopyString(PHeapString dest, PHeapString src);
bool SubString(PHeapString dest, PHeapString src, int pos, int len);
bool ContactString(PHeapString dest, PHeapString src1, PHeapString src2);
bool InsertString(PHeapString dest, int pos, PHeapString src);
bool Deletestring(PHeapString dest, int pos, int len);

# endif

实现文件；主要是代码的实现；

# include "HeapString.h"

PHeapString InitString(void)
{
	PHeapString H = (PHeapString)malloc(sizeof(HeapStirng));

	if (NULL == H)
	{
		cout << "Memory allocate is error! " << endl;
		system("pause");
		exit(0);
	}
	else
	{
		H->str = NULL;
		H->len = 0;

		return H;
	}
}

void ClearString(PHeapString H)
{
	if (NULL != H->str)
	{
		free(H->str);
		H->str = NULL;

		H->len = 0;
	}

	return;
}

void DestroyString(PHeapString * pH)
{
	PHeapString H = *pH;

	free(H->str);
	H->str = NULL;
	H->len = 0;

	free(H);
	H = NULL;

	*pH = NULL;

	return;
}

bool AssignString(PHeapString H, const char * const str)
{
	//释放原内存空间；避免内存泄露；
	ClearString(H);

	//定义迭代变量；
	int len = 0;
	const char * p = str;

	//求字符串长度；
	for (len = 0; *p != '\0'; len++, p++);

	//申请内存空间；
	char * q = (char *)malloc(sizeof(char) * (len + 1));//为了添加字符串结束标识符需要多申请一个字节内存；
	if (NULL == q)
	{
		//返回失败；
		return false;
	}
	else
	{
		//为指针赋值；
		for (int i = 0; i < len; i++)
		{
			q[i] = str[i];
		}
		q[len] = '\0';
		H->str = q;

		//为字符串长度赋值；
		H->len = len;

		//返回成功；
		return true;
	}
}

int LengthString(PHeapString H)
{
	return (H->len);
}

bool EmptyString(PHeapString H)
{
	if (0 == LengthString(H))
	{
		return true;
	}
	else
	{
		return false;
	}
}

bool CopyString(PHeapString dest, PHeapString src)
{
	//释放原内存空间；避免内存泄露；
	ClearString(dest);

	//申请内存空间；
	char * p = (char *)malloc(sizeof(char) * (src->len + 1));
	if (NULL == p)
	{
		//返回失败；
		return false;
	}
	else
	{
		//为指针赋值；
		for (int i = 0; i < src->len; i++)
		{
			p[i] = src->str[i];
		}
		p[src->len] = '\0';
		dest->str = p;

		//为字符串长度赋值；
		dest->len = src->len;

		//返回成功；
		return true;
	}
}

bool SubString(PHeapString dest, PHeapString src, int pos, int len)
{
	ClearString(dest);

	if (pos < 1 || pos > src->len || len < 0 || len > src->len - pos + 1)
	{
		return false;
	}

	char * p = (char *)malloc(sizeof(char) * (len + 1));
	if (NULL == p)
	{
		return false;
	}
	else
	{
		for (int i = 0; i < len; i++)
		{
			p[i] = src->str[i + (pos - 1)];
		}
		p[len] = '\0';
		dest->str = p;

		dest->len = len;

		return true;
	}
}

bool ContactString(PHeapString dest, PHeapString src1, PHeapString src2)
{
	ClearString(dest);

	char * p = (char *)malloc(sizeof(char) * (src1->len + src2->len + 1));
	if (NULL == p)
	{
		return false;
	}
	else
	{
		int i = 0;
		for (; i < src1->len; i++)
		{
			p[i] = src1->str[i];
		} 

		for (; i < src1->len + src2->len; i++)
		{
			p[i] = src2->str[i - src1->len];
		}
		p[src1->len + src2->len] = '\0';

		dest->str = p;
		dest->len = src1->len + src2->len;
		
		return true;
	}
}

bool InsertString(PHeapString dest, int pos, PHeapString src)
{
	if (pos < 1 || pos > dest->len + 1)
	{
		return false;
	}

	dest->str = (char *)realloc(dest->str, sizeof(char) * (dest->len + src->len + 1));

	if (NULL == dest->str)
	{
		return false;
	}
	else
	{
		for (int i = dest->len - 1; i >= pos - 1; i--)
		{
			dest->str[i + src->len] = dest->str[i];
		}
		dest->str[dest->len + src->len] = '\0';

		for (int i = pos - 1; i < pos - 1 + src->len; i++)
		{
			dest->str[i] = src->str[i - (pos - 1)];
		}

		dest->len += src->len;

		return true;
	}
}

bool Deletestring(PHeapString dest, int pos, int len)
{
	if (pos < 1 || pos > dest->len)
	{
		return false;
	}

	for (int i = pos - 1; i < dest->len - len; i++)
	{
		dest->str[i] = dest->str[i + len];
	}

	dest->str = (char *)realloc(dest->str, sizeof(char) * (dest->len - len + 1));
	dest->str[dest->len - len] = '\0';

	return true;
}

Main函数；

# include "HeapString.h"

int main(int argc, char ** argv)
{
	PHeapString H = InitString();
	AssignString(H, "qinjiawei");
	
	PHeapString HH = InitString();
	AssignString(HH, " is a boy!");

	PHeapString HHH = InitString();
	AssignString(HHH, "good ");

	PHeapString dest = InitString();
	SubString(dest, H, 1, 3);
	cout << dest->str << endl;

	if (ContactString(dest, H, HH))
	{
		cout << dest->str << endl;
	}

	if (InsertString(dest, 16, HHH))
	{
		cout << dest->str << endl;
	}

	if (Deletestring(dest, 1, 9))
	{
		cout << dest->str << endl;
	}

	system("pause");
	return 0;
}