https://www.d.umn.edu/~gshute/cs4521/docs/gshute/util/ListDictionary.html
: Class ListDictionary
class
https://learn.microsoft.com/en-us/dotnet/api/system.collections.specialized.listdictionary?view=netframework-4.8.1
ListDictionary Class (System.Collections.Specialized) | Microsoft Learn
Implements IDictionary using a singly linked list. Recommended for collections that typically include fewer than 10 items.
class systemcollectionsspecializedmicrosoftlearn