Collections

• Java doesnt Support Operator Overloading Except for one case i.e + operator it can be used to add number as well as strings.
• So you will have to use methods in java collections, no [] operator or no comparision operators like,< , > , =
• Collections can only work with Objects, so you can't use int, you have to use wrapper class Integer objects.

Building Blocks

• Collections are made of java Arrays and some self referential classes.

class Node<T>{
    T val;
    Node next;
}