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path: root/rushs/evalexpr/src/stack.c
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#include "stack.h"

#include <stdlib.h>

struct stack *stack_push(struct stack *s, int e)
{
    struct stack *new = malloc(sizeof(struct stack));
    new->data = e;
    new->next = NULL;

    new->next = s;
    return new;
}

struct stack *stack_pop(struct stack *s)
{
    if (s == NULL)
    {
        return NULL;
    }

    struct stack *res = s->next;
    free(s);
    return res;
}

int stack_peek(struct stack *s)
{
    return s->data;
}

struct tstack *tstack_push(struct tstack *s, struct token *e)
{
    struct tstack *new = malloc(sizeof(struct tstack));
    new->token = e;
    new->next = NULL;

    new->next = s;
    return new;
}

struct tstack *tstack_pop(struct tstack *s)
{
    if (s == NULL)
    {
        return NULL;
    }

    struct tstack *res = s->next;
    free(s);
    return res;
}

struct token *tstack_peek(struct tstack *s)
{
    return s->token;
}