arduino sort method code example

Example: sort array arduino

// qsort requires you to create a sort function
int sort_desc(const void *cmp1, const void *cmp2)
{
  // Need to cast the void * to int *
  int a = *((int *)cmp1);
  int b = *((int *)cmp2);
  // The comparison
  return a > b ? -1 : (a < b ? 1 : 0);
  // A simpler, probably faster way:
  //return b - a;
}

void setup() {
  // The array
  int lt[6] = {35, 15, 80, 2, 40, 110};
  // Number of items in the array
  int lt_length = sizeof(lt) / sizeof(lt[0]);
  // qsort - last parameter is a function pointer to the sort function
  qsort(lt, lt_length, sizeof(lt[0]), sort_desc);
  // lt is now sorted
}

void loop()
{
}