数据结构 --栈的实现

#ifndef STACK_H
#define STACK_H

#include "stdlib.h"
#define STACK_INIT_SIZE 100
#define STACKINCREMENT  10
#define OK 1
#define OVERFLOW  -2
#define Status  bool
#define TRUE  1
#define FALSE 0
#define ERROR 0

template <typename SElemType>
class SqStack
{
public:
	SElemType *base;
	SElemType *top;
	int stacksize;

    Status InitStack();
    Status DestroyStack();
    Status ClearStack();
	Status StackEmpty();
	Status Push(SElemType e);
	Status GetTop(SElemType &e);
	Status Pop(SElemType &e);
	int StackLength();
	Status StackTraverse(Status (* visit)(SElemType e));
};

template <typename SElemType>
Status SqStack<SElemType>::InitStack()
{
	base = (SElemType *)malloc(STACK_INIT_SIZE * sizeof(SElemType));
	if (!base)  exit(OVERFLOW);
    top = base;
	stacksize = STACK_INIT_SIZE;
	return OK;
}

template <typename SElemType>
Status SqStack<SElemType>::DestroyStack()
{
	free (base);
	base = top = NULL;
	return OK;
}

template <typename SElemType>
Status SqStack<SElemType>::ClearStack()
{
	top = base;
	return OK;
}

template <typename SElemType>
Status SqStack<SElemType>::StackEmpty()
{
	if (top == base)
	{
		return TRUE;
	}
	else
	{
		return FALSE;
	}
}

template <typename SElemType>
Status SqStack<SElemType>::Pop(SElemType &e)
{
	if (base == top)  return ERROR;
	e = *--top;
	return OK;
}

template <typename SElemType>
Status SqStack<SElemType>::Push(SElemType e)
{
	if (top - base >= stacksize)
	{
		base = (SElemType *)realloc(base, 
			(stacksize + STACKINCREMENT) * sizeof(SElemType));
		if (!base) exit(OVERFLOW);
		top = base + stacksize;
		stacksize += STACKINCREMENT;
	}
	*top ++ = e;
	return OK;
}

template <typename SElemType>
int SqStack<SElemType>::StackLength()
{
	return top - base;
}

template <typename SElemType>
Status SqStack<SElemType>::GetTop(SElemType &e)
{
	if (base == top) return ERROR;
	e = *(top - 1);
	return OK;
}

template <typename SElemType>
Status SqStack<SElemType>::StackTraverse(Status (* visit)(SElemType e))
{
	if (base == top) return ERROR;
	SElemType *pSElemType = top;
	while (base < pSElemType)
	{
		pSElemType --;
		visit(*pSElemType);
	}
	return OK;
}

#endif