What is a data structure that is disordered and permits repetitions?

Question

Is there any "formal name" for the structure data with the following functions:

• set / group that allows repetition
• unordered (order doesn't matter)

For example, a list is an ordered set / group with repetitions.

There {2,2,2,2,3,3,3,3,4,4,4,7,6,5,6}is no value in the order set; therefore, an effective implementation method is established using 2-dimensional arrays {[2,4],[3,4],[4,3],[7,1],[6,2],[5,1]}.

I ask if there is any official name?

Answer 1

You may be referring to Multiset .

This is a collection that allows multiple instances of an element.