#ifndef STACK_H
#define STACK_H

#define STACK_CAPACITY 61

typedef struct {
    long long items[STACK_CAPACITY];
    int count;
} Stack;

static inline void stack_init(Stack *stack)
{
    stack->count = 0;
}

static inline int stack_empty(const Stack *stack)
{
    return stack->count == 0;
}

static inline int stack_size(const Stack *stack)
{
    return stack->count;
}

static inline int stack_push(Stack *stack, long long value)
{
    if (stack->count == STACK_CAPACITY) return 0;
    stack->items[stack->count++] = value;
    return 1;
}

static inline void stack_pop(Stack *stack)
{
    if (stack_empty(stack)) return;
    stack->count--;
}

static inline long long stack_top(const Stack *stack)
{
    return stack->items[stack->count - 1];
}

#endif