is the process in which the compiler replaces the generic types with their bound or object.
Plain old java object (POJO)
is a simple java object that does not require any fancy library in classpath other than the JVM to be instantiated.
Single responsibility principle
A class should have only a single responsibility (i.e. changes to only one part of the software's specification should be able to affect the specification of the class).
Software entities should be open for extension, but closed for modification.
Liskov substitution principle
Objects in a program should be replaceable with instances of their subtypes without altering the correctness of that program.
Interface segregation principle
Many client-specific interfaces are better than one general-purpose interface.
Dependency inversion principle
One should depend upon abstractions, concretions.
Given a balanced BST
4 2 5 1 3
Depth First Traversals
Inorder (Left, Root, Right) : 1 2 3 4 5
Preorder (Root, Left, Right) : 4 2 1 5 3
Postorder (Left, Right, Root) : 1 3 2 5 4
Breadth First 4 2 5 1 3
Bubble sort. Time O(N^2) Space O(1)
Selection sort. Time O(N^2) Space O(1)
Merge sort. Time O(N log(N) Space O(1)
Quick sort. Time average O(N log(N). Worst case O(N^2). Space O(log(N)).