#include <stdio.h>
#include <assert.h>
#include <stdlib.h>

typedef int bool;
#define true 1
#define false 0

struct stack {
    int top;
    int *data;
    int size;

};

void stack_push(struct stack *s, int e);
int stack_pop(struct stack *s);
bool stack_empty(struct stack *s);
bool stack_full(struct stack *s);
void stack_clear(struct stack *s);
void stack_free(struct stack* s);

struct stack* stack_create(int size) {
    struct stack* s = (struct stack*)malloc(sizeof(struct stack));
    s->top = -1;
    s->data = (int*)malloc(sizeof(int)*size);
    s->size = size;
    return s;
}

void stack_push(struct stack *s, int e) {
    assert(!stack_full(s));
    s->data[++s->top] = e;
}

int stack_pop(struct stack *s) {
    assert(!stack_empty(s));
    return s->data[s->top--];
}

bool stack_empty(struct stack *s) {
    return (s->top == -1);
}

bool stack_full(struct stack *s) {
    return (s->top == s->size - 1);
}

void stack_clear(struct stack *s) {
    s->top = -1;
}

void stack_free(struct stack* s) {
    free(s->data);
    free(s);
}

int main( int argc, char *argv[] ) {
    struct stack* s = stack_create(10);

    for(int i = 0; !stack_full(s); i++) {
        stack_push(s, i);
    }

    while(!stack_empty(s)) {
        printf("%d\n",stack_pop(s));
    }

    stack_free(s);
    s = NULL;

	return 0;
}