If you examine the modification more closely, it is just finding the list that would exhibit worst case performance - once created, that list would always exhib

If you examine the modification more closely, it is just finding the list that would exhibit worst case performance - once created, that list would always exhibit the worst case as a constant list. Once you have the resulting list, the indices are sorted, then assigning each num_solid value to that index would result in the list being constant, and then could be sorted to give such worst case behavior. I wish the article was more clear on this.