Basics of Programming for beginners

Introduction

Computer programming is a set of instructions through which one tells

the computer to do the desired task. This set of instructions written in

human readable computer language is called Source Code. Every program

has two parts namely code and data. There are two models of

programming namely Structured Programming and Object Oriented

Programming. In Structured Programming codes are executed one after

one in a serial fashion. Example for this is ‘C’ Language. In object

oriented programming, data is accessed through objects. There is no

single flow. Here objects freely interact with one another by passing

messages.

Problem Solving Techniques

To develop the solution for the given problem, the following programming

techniques are used.

Problem solving techniques

i) Algorithm-

Algorithm is a step by step procedure to solve any problem.

ii) Flow Charts-

Flow Chart is a graphical represantation of the steps involved in a programme.

iii) Pseudo codes-

These are the instructions written in ordinary English using

mathematical and logical symbols to display the program logic.

iv) Decision Tables-

A decision table consists of many independent conditions with several

actions, written in table format to solve the given problem.

Properties of an Algorithm

i. Finiteness: An algorithm must always terminate after a finite

number of steps.

ii. Definiteness: Each step must be clearly defined that actions

carried out must be unambiguous.

iii. Input: Input should be provided at the beginning of algorithm.

iv. Output: Algorithm must produce on or more output.

v. Effectiveness: All the operations defined must be sufficiently basic

that they can be done exactly in finite length of time manually.

Basic Statements Used and Examples

i. Algorithm always begins with the word ‘Start’ and ends with the word

‘Stop’

ii. Step wise solution is written in distinguished steps. This is as shown in

example 1

Start

Step 1:

Step 2:

Step 3:

.

.

.

Step n:

End

Ex.:- Calculate the greater number between three numbers.

Ans.-

1. Start the Algorithm.

2. Take three numbers from the user.

3. If the first number greater than second number and the first number is greater than the third number, then display first number is greatest.

4. Else if second number is greater than first number and first number is greater than third number,then display second number is greatest.

5. Else third number is greatest.

6. Stop the algorithm