学步园

/*
	两栈共享空间
	作者：S_hmily
	日期：2011年8月31日
	编译环境：VC6.0++
	栈1空	S->top1 == -1
	栈2空	S->top2 == MaxSize
	栈满	S->top1 + 1 == S->top2
*/
/************************************************/
#include <stdio.h>
/************************************************/
#define MaxSize 20 
#define OK      1      
#define ERROR   0      
#define TRUE    1      
#define FALSE   0    
typedef int     ElemType;  
typedef int     Status;  
  
typedef struct {  
    ElemType    data[MaxSize];  
    int         top1;                    //栈顶指针1  
    int         top2;					 //栈顶指针2  
}Stack,  *pStack;  
/************************************************/
//初始化
Status InitStack(pStack S)
{
	S->top1 = -1;
	S->top2 = MaxSize;
	return OK; 
}
/************************************************/
//压栈
Status Push_Stack(pStack S, ElemType e, int stackNumber)
{
	if (S->top1+1 == S->top2)
		return ERROR;
	switch(stackNumber)
	{
		case 1:		S->data[++S->top1] = e;		break;
		case 2:		S->data[--S->top2] = e;		break;
	}
	return OK;
}
/************************************************/
//出栈
Status Pop_Stack(pStack S, ElemType *e, int stackNumber)
{
	if (1 == stackNumber)
	{	//栈1空
		if (-1 == S->top1)		
			return ERROR;
		*e = S->data[S->top1--];
	}
	else if (2 == stackNumber)
	{
		if (MaxSize == S->top2)
			return ERROR;
		*e = S->data[S->top2++];
	}
	return OK;
}
/************************************************/
//输出栈中所有元素
Status DispStack(pStack S, int stackNumber)
{
	int i;
	if (1 == stackNumber)
	{
		if (-1 == S->top1)
			return ERROR;

		printf("栈1中的元素为：");
		for (i=0; i<=S->top1; ++i)
			printf("%d ", S->data[i]);
	}
	else if (2 == stackNumber)
	{
		if (MaxSize == S->top2)
			return ERROR;
		printf("栈2中的元素为：");
		for (i=MaxSize-1; i>=S->top2; --i)	
			printf("%d ", S->data[i]);
	}
}
/************************************************/
int main(void)
{
	Stack S;
	ElemType e;
	InitStack(&S);
	Push_Stack(&S, 1, 1);
	Push_Stack(&S, 2, 1);
	Push_Stack(&S, 3, 1);
	Push_Stack(&S, 4, 1);
	Push_Stack(&S, 5, 1);
	Push_Stack(&S, 6, 1);
	Pop_Stack(&S, &e, 1);
//------------------------------
	Push_Stack(&S, 10, 2);
	Push_Stack(&S, 9, 2);
	Push_Stack(&S, 8, 2);
	Push_Stack(&S, 7, 2);
	DispStack(&S, 1);
	return 0;
}
/************************************************/