quicksort.ccash

func partition(mut []int32 arr, const uint32 low, const uint32 high) uint32 {
    const int32 pivot := arr[high];
    mut uint32 i := low - uint32(1);

    for mut uint32 j := low; j <= high - uint32(1); j++ {
        if arr[j] < pivot {
            i++;
            arr[i] :=: arr[j];
        }
    }

    arr[i + uint32(1)] :=: arr[high];
    return i + uint32(1);
}

func quicksort(mut []int32 arr, const uint32 low, const uint32 high) {
    if low < high {
        const uint32 pivot := partition(arr, low, high);
        quicksort(arr, low, pivot - uint32(1));
        quicksort(arr, pivot + uint32(1), high);
    }
}

func printArray(const []int32 arr) {
    printf("[");
    // for const uint32 i in 0..arr.length { // Ranges are to be implemented...
    for mut uint32 i := uint32(0); i < arr.length; i++ {
        printf("%d, ", arr[i]);
    }
    printf("]\n");
}

func main() {
    mut []int32 arr := [10, 7, 8, 9, 1, 5];
    printf("Original array: ");
    printArray(arr);

    quicksort(arr, uint32(0), arr.length);
    printf("Sorted array: ");
    printArray(arr);
}