1. Introduction to Computer Programming CS 126 Lecture 2 Zeke Maier

2. Plan for Today Questions Administrivia Course Census Results Java Introduction Assignment CEC Accounts

3. Questions: Jobs Job market is tight right now Google, Microsoft, Boeing, Monsanto… FBI, NSA, smaller firms, start a new company! PositivesNegatives Job SatisfactionActivity $50,000Monotony Still GrowingCeiling

4. Questions: Job Skills Multitude of languages –.NET, Java, C/C++, Ruby… – HTML, CSS, Javascript, ActionScript/Flash,.NET, Ruby, PHP, Python… – SQL Source Revision Control –Subversion, CVS, GIT Other –Projects, Aptitude, Coding Style, Methodology

5. Administrivia http://students.cec.wustl.edu/~ejm3/ –Teaching Assistant schedule –Telesis for grades –Calendar updated –AIM account –Assignment cover sheet

6. Course Census Results

9. Course Goals “Understand how computers operate to strengthen my everyday interactions” “Gain a basic understanding of programming to evaluate potential future endeavors” Additional Comments “Can I do well without previous programming experience?”

10. Languages Syntax –Rules of writing structure Semantics –Meaning of what is written class Hello { //My first program! public static void main(String args[]) { system.out.println(“Hello, World!”); }

11. Programming Languages A language for describing computer computations –High level languages Description: abstraction of low level languages Examples: Java, C++,… –Low level languages Description: 1s and 0s, computer executable Examples: assembly & machine code

12. High Level Languages: Basic Elements Primitives –Numbers, characters, strings, addition… Means of combination –x=3+4; Means of abstraction –Data abstraction (Facebook profile) Means of capturing common patterns –Inheritance

13. High to Low Level

14. Java Object Oriented Programming Language –Programs are a collection of communicating objects Class = type of object Object = instantiation of class Class –Models something… –Consists of: Data members Methods

15. Program Sequence of instructions which specify a computation –Take in input –Perform operations –Produce output –Testable

16. Debugging Process of tracking down and correcting bugs –Compile-time errors Syntax –Run-time errors Exceptions –Logic errors Semantic Experimental debugging

17. Assignment Lab 0 to be done in lab sections today Readings –Friday AD Chapter 1 KG Notes