qsort and bsearch

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

int comp(const void *p1, const void *p2) {
  const float nr1 = *(const float*)p1;
  const float nr2 = *(const float*)p2;
  return nr1 - nr2;
}

int main(void) {
  unsigned n;
  scanf("%u", &n);
  float *arr = (float*)calloc(sizeof(float), n), x;
  if (arr == NULL) {
    perror("");
    exit(EXIT_FAILURE);
  }
  for (unsigned i = 0; i < n; i++) {
    scanf("%f", arr + i);
  }

  qsort(arr, n, sizeof(float), comp);

  for (unsigned i = 0; i < n; i++) {
    printf("%g ", arr[i]);
  }
  puts("");

  scanf("%f", &x);
  float *p = bsearch(&x, arr, n, sizeof(float), comp);
  if (p != NULL) {
    printf("%g found at pos %ld\n", x, p - arr);
  } else {
    printf("%g not found!\n", x);
  }

  free(arr);
  return 0;
}