#include<stdio.h>
#include<malloc.h>
#include<conio.h>

#define ERROR 0
#define TRUE 1
#define FALSE 0
#define OK 1
#define EQUAL 1
#define OVERFLOW -1
#define STACK_INIT_SIZE 100
#define STACKINCREMENT 10

typedef int Status ;

struct STU
{
	char name[20];
	char stuno[10];
	int age;
	int score;
};
typedef struct STU SElemType;

struct STACK
{
	SElemType *base;
	SElemType *top;
	int stacksize;
};

typedef struct STACK SqStack;
typedef struct STACK *pSqstack;

Status InitStack ( SqStack  **S );
Status DestroyStack ( SqStack *S );
Status ClearStack ( SqStack *S );
Status StackEmpty ( SqStack S );
int StackLength ( SqStack S );
Status GetTop ( SqStack S,SElemType *e );
Status Push ( SqStack *S,SElemType e );
Status Pop ( SqStack *S,SElemType *e );
Status StackTraverse ( SqStack S,Status ( *visit ) () );

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

Status DestroyStack ( SqStack *S )
{
	free ( S->base );
	free ( S );
}

Status ClearStack ( SqStack *S )
{
	S->top=S->base;
}

Status StackEmpty ( SqStack S )
{
	if ( S.top==S.base ) return TRUE;
	else
		return FALSE;
}

int StackLength ( SqStack S )
{
	int i;
	SElemType *p;
	i=0;
	p=S.top;
	while ( p!=S.base )
	{
		p++;
		i++;
	}
}

Status GetTop ( SqStack S,SElemType *e )
{
	if ( S.top==S.base ) return ERROR;
	*e=* ( S.top-1 );
	return OK;
}

Status Push ( SqStack *S,SElemType e )
{
	/*
	 if(S->top - S->base>=S->stacksize)
	  {

	    S->base=(SElemType *) realloc(S->base,
	       (S->stacksize + STACKINCREMENT) * sizeof(SElemType));
	    if(!S->base)exit(OVERFLOW);
	    S->top=S->base+S->stacksize;
	    S->stacksize += STACKINCREMENT;
	  }
	 */

	* ( S->top++ ) =e;
	return OK;
}

Status Pop ( SqStack *S,SElemType *e )
{
	if ( S->top==S->base ) return ERROR;
	*e=*--S->top;
	return OK;
}

Status StackPrintElem ( SElemType * e )
{
	printf ( "%s  %s  %d  %d\n",e->name,e->stuno,e->age,e->score );
}
Status StackTraverse ( SqStack S,Status ( *visit ) () )
{
	while ( S.top!=S.base )
		visit ( --S.top );
}

main()
{
	SElemType e;
	SqStack *Sa;

	clrscr();

	printf ( "\n\n-------------------SqStack Demo is running...----------------\n\n" );
	printf ( "First is Push function.\n" );

	InitStack ( &Sa );

	strcpy ( e.name,"stu1" );
	strcpy ( e.stuno,"100001" );
	e.age=80;
	e.score=1000;

	printf ( "   Now Stack is Empty.\n" );
	StackTraverse ( *Sa,StackPrintElem );

	Push ( Sa,e );

	printf ( "   Now Stack has one element.\n" );
	StackTraverse ( *Sa,StackPrintElem );

	strcpy ( e.name,"stu3" );
	strcpy ( e.stuno,"100002" );
	e.age=80;
	e.score=1000;
	Push ( Sa,e );
	printf ( "   Now Stack has another element.\n" );
	StackTraverse ( *Sa,StackPrintElem );

	printf ( "   Now Pop Stack,the top elem put into variable e.\n" );
	Pop ( Sa,&e );
	printf ( "%s\n%s\n%d\n%d\n",e.name,e.stuno,e.age,e.score );

	printf ( "   Let's see the left of Stack's elem:\n" );
	StackTraverse ( *Sa,StackPrintElem );

	getch();
	printf ( "\n\n\nWelcom to visit http://zmofun.topcool.net\n\n" );
}