面試被問到的基礎資料結構問題

Difference between List and Set:

List	Set
1. The List is an ordered sequence.	1. The Set is an unordered sequence.
2. List allows duplicate elements	2. Set doesn’t allow duplicate elements.
3. Elements by their position can be accessed.	3. Position access to elements is not allowed.
4. Multiple null elements can be stored.	4. Null element can store only once.
5. List implementations are ArrayList, LinkedList, Vector, Stack	5. Set implementations are HashSet, LinkedHashSet.

 

MAP:

A Map is a type of fast key lookup data structure that offers a flexible means of indexing into its individual elements.
Indices into the elements of a Map are called keys. 

These keys, along with the data values associated with them, are stored within the Map. Each entry of a Map contains exactly one unique key and its corresponding value.