Chapter 1, Lesson 1

Welcome to Beginners Programming.

First thing’s first, English is not my native language so please excuse me for my bad English.

There are two main ways to write a computer program, Graphically, by using flowcharts and by using computer programming languages, such as BASIC, C/C++, Pascal, C#, Java, etc..

But let us learn the basics of programming. The first thing you have to know is how did computer programming came into being. It all started with algorithm. Algorithm [al-guh-rith-uhm] (n.) It is a step by step instructions to solving a given task. One good example is the recipe.

Recipe for Making a Coffee

1. Get the Coffee Jar
2. Scoop a bit of coffee into coffee cup.
3. Scoop a bit of sugar into coffee cup.
4. Pour hot water into coffee cup
5. Stir as desired
6. Drink the coffee when ready.

We have been using algorithms all our life and we have not notice it. Like how to tie your shoe laces. When you buy your first microwave oven, or a gadget, you read the instructions on how to operate, and there you will see a series of steps (algorithm)

The algorithm is then converted to a graphic representation, using symbols interconnected with flow lines, of the successive steps in a procedure or system. It is called Flowchart.

Basic flowchart symbols

Lets do a little exercise.

Problem: Given the 3 quiz grades of the student, Quiz1: 80, Quiz2:82, Quiz3:78. Write and algorithm and draw a flowchart that would compute for the average grade and display your answer.

Algorithm:

1. let x1 = 80, x2 = 82, x3 = 78
2. let sum = x1 + x2 + x3
3. let average = sum / 3
4. display the average

Flowchart:

Another example using Perl program.

graph { flow: south; } node.start { shape: rounded; fill: #ffbfc9; } node.question { shape: diamond; fill: #ffff8a; } node.action { shape: rounded; fill: #8bef91; } [ Lamp doesn't work ] { class: start } --> [ Lamp\n plugged in? ] { class: question; } -- No --> [ Plug in lamp ] { class: action; } [ Lamp\n plugged in? ] --> [ Bulb\n burned out? ] { class: question; } -- Yes --> [ Replace bulb ] { class: action; } [ Bulb\n burned out? ] -- No --> [ Buy new lamp ] { class: action; }

Wikipedia – Flowchart http://en.wikipedia.org/wiki/Flowchart

On the left side is the Perl Code or program in which just a series of text instructions (algorithm) to be executed. And on the right side is the graphical representation (flowchart).

As you can see, the program or series of instructions is clearly understood using graphical flowchart.

By the way, I would also inform you that the language we will be using is the C Language. And i would assume that you have a little knowledge in C Syntax. You can search the net for C Syntax.

In our next lesson, we will have simple problems, flowchart making and Create a C program translated from flowchart. If you learn this simple steps , you can create programs using any programming language you want. At Beginners Programming, we will be your guide.

-End of lesson 1 Beginners Programming