int quick_sort_r(int array[], int start, int end) {
if (start < end) {
int j = quick_sort_partion(array, start, end);
quick_sort_r(array, start, j - 1);
quick_sort_r(array, j + 1, end);
}
return 0;
}
static void quick_sort_r(register int a[], register int left, register int right) {
//if array is empty or only 1 element sort is redudant
if (left < right && !is_sorted(a, left, right)) {
if ((right - left) < THRESHOLD) {
insertion_sort_sub(a, left, right + 1);
return;
}
//get the random number
register int random = rand() % (right - left + 1) + left;
//swap random to the last
swap((a + random), (a + right));
//get the pivot index
register int pivot_index = random_partition(a, left, right);
//recursively run the sort again with half-left and half-right of the array
quick_sort_r(a, left, pivot_index - 1);
quick_sort_r(a, pivot_index + 1, right);
}
}
void quick_sort_random(register int a[], register int length) {
quick_sort_r(a, 0, length - 1);
}
int quick_sort(int array[], int size) {
quick_sort_r(array, 0, size);
return 0;
}
