Computer Programming (BCT 1113) Introduction To Programming Computer Programming Concept Problem Solving Flowchart Structure Programming Design Implementation Documentation Testing and Debugging

Objectives Understand Computer Programming Concept Problem Solving Design Flowchart Structure Programming Design Implementation of programming Documentation in programming Testing and Debugging programming

Why learn programming? To be a creator - Programming is like having access to the absolute best set of legos in the world in almost unlimited qualities Automate Away Daily Drudgery - Programmers are famous for being lazy--in fact, being lazy is one reason people are drawn to programming. After all, why do something routine and repetitive when you could have your computer do it for you? Improve Your Computer Literacy and Know the Answer to the "Why" Questions - People are often frustrated by technology when it fails. Although operating systems such as Windows have become much more stable, there are still many security holes exploited every day. For a non-programmer, these issues are mysteries: the machine that never makes mistakes is full of problems, and who knows why? 

How to learn programming? Look at the Example Code Don't Just Read Example Code--Run It Write your Own Code as Soon as Possible Learn to Use a Debugger Seek out More Sources

Types of programming language Procedural programming language – Fortran, BASIC Structural programming language – C, ADA, Pascal Object oriented programming language – JAVA, VB, C#

History of programming language Before 1940: The Jacquard loom, invented in 1801, used holes in punched cards to represent sewing loom arm movements in order to generate decorative patterns automatically. 1940: first recognizably modern, electrically powered computers were created 1950: 1960 – FORTRAN, LISP, COBOL 1967 – 1978: establishing fundamental paradigm – Simula, C, Prolog, The 1980s: consolidation, modules, performance – ADA, C++, Perl The 1990s: the Internet age – PYTHON, VB, JAVA, PHP, ASP

Programming Program: self-contained set of instructions used to operate a computer to produce a specific result Also called software Programming: the process of writing a program, or software

Programming Machine language programs, also called executables, consist of binary instructions Each instruction has two parts: Instruction part: the operation to be performed; also called an opcode Address part: memory address of the data to be used Each class of computer has its own particular machine language

Programming structure Algorithm: the step-by-step sequence of instructions that describe how the data is to be processed to produce the desired output Programming: the translation of the selected algorithm into a language the computer can use Pseudocode: English-like phrases used to describe the algorithm Formula: description of a mathematical equation Flowchart: diagram showing the flow of instructions in an algorithm Flowcharts use special symbols

Flowchart

Flowchart

Flowchart: example Figure 1.12 Flowchart for calculating the average of three numbers.

Pseudo code: example Read NUMBER1, NUMBER2, NUMBER3 Compute AVERAGE as ((NUMBER1+NUMBER2+NUMBER3)/3) Write (Display) AVERAGE

Implementation Write a program that could display following information #include <iostream> using namespace std; int main() { cout << “Umar"; cout << "\n123 Jalan Cempaka"; cout << "\nChukai, Kemaman"; cin.ignore(); // this line is optional, it is used // to keep the program from ending on Microsoft // systems/compilers so the user can see the output return 0; }

Process of Writing a Program Identify problems – requirements, specification Design a solution – pseudo code, flowchart Program Code - translating the design into an actual program, written in some form of programming language Compile - process of turning the program written in some programming language into the instructions made up of 0's and 1's that the computer can actually follow Debug - task of looking at the original program, identifying the mistakes, correcting the code and recompiling it

Documentation in Programming /* my second program in C++ with more comments */ #include <iostream> using namespace std; int main () { cout << "Hello World! "; // prints Hello World! cout << "I'm a C++ program"; // prints I'm a C++ program return 0; }

Testing & Debugging All written program must be tested to ensure it is correctly run and suit requirements. Debugging is the process of locating and fixing or bypassing bugs (errors) in computer program code or the engineering of a hardware device. To debug a program or hardware device is to start with a problem, isolate the source of the problem, and then fix it

Common programming mistakes Starting to write the program before fully understanding the requirements and the algorithm to be used Undeclared variables Uninitialized variables Using a single equal sign to check equality Undeclared Functions Extra Semicolons Misusing the && and || operators

REFERENCES http://www.cprogramming.com/whyprogram.html http://www.giac.org/cissp-papers/97.pdf http://www.cs.bham.ac.uk/~rxb/java/intro/2programming.html