栈 I

/*stack.h*/

#define STACK_TYPE int

void push(STACK_TYPE value);

void pop(void);

STACK_TYPE top(void);

int is_empty(void);

int is_full(void);

/*stack.c*/

#include "stack.h"
#include <assert.h>

#define STACK_SIZE 100

static STACK_TYPE stack[STACK_SIZE];
static int top_element = -1;


void
push(STACK_TYPE value)
{
        assert(is_full != 0);
        top_element++;
        stack[top_element] = value;
}

void
pop(void)
{
        assert(is_empty != 0);
        top_element--;
}

STACK_TYPE
top(void)
{
        assert(is_empty != 0);
        return (stack[top_element]);
}

int
is_empty(void)
{
        if (-1 == top_element)
                return 0;
        else
                return -1;
}

int
is_full(void)
{
        if (STACK_SIZE - 1 == top_element)
                return 0;
        else
                return -1;
}

/*test.c*/

#include <stdio.h>
#include "stack.h"

int
main(void)
{
        int a[10] = {1,3,5,7,9,0,2,4,6,8};
        int len = sizeof(a)/sizeof(a[0]);
        int i;

        printf("stack is_empty: %d\n", is_empty());
        printf("stack is_full: %d\n", is_full());
        printf("\n");

        for (i = 0; i < len; i++) {
                push(a[i]);
                printf("%d,", top());
        }
        printf("\n");

        printf("stack is_empty: %d\n", is_empty());
        printf("stack is_full: %d\n", is_full());
        printf("\n");

        for (i = 0; i < len; i++) {
                printf("%d,", top());
                pop();
        }
        printf("\n");

        printf("stack is_empty: %d\n", is_empty());
        printf("stack is_full: %d\n", is_full());
        printf("\n");

        return 0;
}

/*output*/

stack is_empty: 0
stack is_full: -1

1,3,5,7,9,0,2,4,6,8,
stack is_empty: -1
stack is_full: -1

8,6,4,2,0,9,7,5,3,1,
stack is_empty: 0
stack is_full: -1