How can I make this version of Bucket Sort using recursion?

Question

Currently what this function is doing is sorting an array using BucketSort. The array is going to be with numbers between 0 and 999. However instead of that I want to split every bucket into 10 other buckets until i am left with single digits, so basically 3 times. However I struggle to cycle through every bucket. Does anybody have any idea how to do this?

void bucketSort(int arr[], int size, int divider)
{
    int max, bucket = 10, i, j, k;
    int B[bucket][size];
    int B_size[10];
    max = getMax(arr, size);

    for(i = 0; i < 10; i++)
    {
        B_size[i] = 0;
    }
    //insert element in buckets
    for(i = 0; i < size; i++)
    {
        j = floor( arr[i] / divider );
        B[j][B_size[j]] = arr[i];
        B_size[j]++;
    }

    //sort elements in buckets
    for(i = 0; i < bucket; i++)
    {
        quickSort(B[i], 0, B_size[i] - 1);
    }
    //bring elements back
    k = 0;
    for(i = 0; i < bucket; i++)
    {
        for(j = 0; j < B_size[i]; j++)
        {
            arr[k++] = B[i][j];
        }
    }
}

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