// description: based on `geeksforgeeks` description Stack is a linear data structure which follows a particular order in which the operations are performed.
// The order may be LIFO(Last In First Out) or FILO(First In Last Out).
// details:
// Stack Data Structure : https://www.geeksforgeeks.org/stack-data-structure-introduction-program/
// Stack (abstract data type) : https://en.wikipedia.org/wiki/Stack_(abstract_data_type)
// author [Milad](https://github.com/miraddo)
// see stacklinkedlistwithlist.go, stackarray.go, stack_test.go