lib/stack.c


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#include "stack.h"

void stack_push(ll_t **q, v_t x) {
  ll_t *nq = malloc(sizeof(ll_t));
  nq->x = x;
  nq->next = *q;

  *q = nq;
}

void stack_push_d(dll_t **q, double x) {
  dll_t *nq = malloc(sizeof(dll_t));
  nq->x = x;
  nq->next = *q;

  *q = nq;
}

v_t stack_pop(ll_t **q) {
  ll_t *old_q = *q;

  *q = old_q->next;
  v_t x = old_q->x;

  free(old_q);

  return x;
}

double stack_pop_d(dll_t **q) {
  dll_t *old_q = *q;

  *q = old_q->next;
  double x = old_q->x;

  free(old_q);

  return x;
}