Prepare example of using math modul! secondprogram.py A module is a file containing Python definitions and statements. The file name is the module name with the suffix .py appended.

Edsger Dijkstra:

Computer science is no more about computers than astronomy is about telescopes.

Abstraction is an important paradigm for solving complex problems.

Typical example is an abstract data type stack.

This while loop finishes if counter > 10 or done equals True.

Python provides loop and conditional statements.

Loop sttements:

1. while loop
2. for loop

Conditional statements:

1. if statement
2. ifelse statement

len is a metod.

Lists are naturally ordered by adding and removing elements.

Relation between operator // and %.

a = (a // b) * b + a % b

Variable = Expression

An Expression is evaluated and the it's value (reference to an object) is assigned to a Variable

The operator module exports a set of efficient functions corresponding to the intrinsic operators of Python. For example, operator.add(x, y) is equivalent to the expression x+y.

len(s) is built-in function

Return the length (the number of items) of an object. The argument may be a sequence (such as a string, bytes, tuple, list, or range) or a collection (such as a dictionary, set, or frozen set).

Collection is an object that contains other objects.

The main OOP concepts:

1. an object as a model of a real object
2. a class as a factory for objects or as a template that defines the structure of objects from this class and behavior of objects from this class
3. an object as an instance of a class
4. a method with or without parameters describes the behavior of instances
5. calling or invoking method

The return value is None.

For newbies I can recommend video lectures by Charles Severence.

Programming languages provide control structures for sequential, conditional and iterative performing partial actions.

Data type = set of values + set of operations.

Data types are glasses for interpretation of binary data.

This is programming in the narrow sense of the word. Programming in a broader sense contains also analysis of the problem, design the solution, testing, debugging, maintaining.

Algorithm is a transformation of valid input data to corresponding otput data.

Features of a good algorithms:

Precision– the steps are precisely stated(defined).

Uniqueness– results of each step are uniquely defined and only depend on the input and the result of the preceding steps.

Finiteness– the algorithm stops after a finite number of instructions are executed.

Input– the algorithm receives input.

Output– the algorithm produces output.

Generality– the algorithm applies to a set of inputs.

1. The study of algorithms and data structures makes you better algorithmic problem solver.
2. For algorithms implementation is used Python programming language. Review this language is not exhaustive. For more details I refer you to the parallel course Python Basics.

There are general design techniques (strategies) for solving algorithmic problem:

1. Brute Force
2. Backtracking
3. Greedy approach
4. Dynamic Programming
5. Divide and Conquer

Object oriented programming is based on creating models of the problem domain.

Python is object oriented language that is used in this course for algorithms implementation.

Abstract data type defines the actions that can be done with data without implementations. E.g. stack

Iteration, selection and sequence are three important control structures.