fib dyn

#include <stdio.h>
#include <stdlib.h>
#include <stdint.h>
#define CHUNK (1 << 9)

void checkAlloc(void *p) {
  if (p == NULL) {
    perror("");
    exit(EXIT_FAILURE);
  }
}

typedef struct {
  int len, mem;
  uint64_t *at;
} DynArr;

DynArr mkArr(int ini) {
  DynArr arr = {ini, ini, NULL};
  if (ini) {
    arr.at = calloc(sizeof(uint64_t), ini);
  }
  return arr;
}

void addToArr(DynArr *arr, uint64_t x) {
  if (arr->len == arr->mem) {
    arr->mem += CHUNK;
    arr->at = realloc(arr->at, sizeof(uint64_t) * arr->mem);
    checkAlloc(arr->at);
  }
  arr->at[arr->len++] = x;
}

void printArr(const DynArr *const arr) {
  for (int i = 0; i < arr->len; i++) {
    printf("%lu ", arr->at[i]);
  }
  puts("");
}

int main(void) {
  DynArr fib = mkArr(2);
  fib.at[1] = 1;

  int term;
  scanf("%d", &term);
  for (int i = 2; i < term; i++) {
    int newElem = fib.at[i - 2] + fib.at[i - 1];
    addToArr(&fib, newElem);
  }

  printArr(&fib);
  free(fib.at);
  return 0;
}