Page 17 - Computer Class 06

Hence, an algorithm is a list of step-by-step instructions that are followed in order to

get a task done. Each instruction should be very simple to that a computer can
understand exactly what it needs to do.

Let us write an algorithm to find the greater of two numbers (A and B). The steps for
this problem is as given below.

Step 1 : Start
Step 2 : Read the values of ‘X’ and ‘Y’.

Step 3 : Compare these values to determine if is greater than .X Y

Step 4 : Stop

This algorithm explains how we follow the steps in problem solving.
1. Formulating the problem and deciding the input data, if any.

2. Identifying the various steps of computation that are must for the solution.

3. Identifying the points of decision, i.e., under what circumstances a particular
operation is to be performed.

4. Knowing the expected results and when to obtain the output.

Flowchart

Flowchart is a graphical representation of an algorithm. Programmers often use it as
program-planing tool to solve a problem. It makes use of symbols which are

connected among them to indicate the flow of information and processing. The
process of drawing a flowchart from algorithm is known as flowcharting .

The first design of flowchart goes back to 1945 which was designed by John Von Neumann.

Flowchart Symbols

Flowcharts use special shapes to represent different types of actions or steps in a
process. Lines and arrows show the sequence of the steps and the relationships
among them. These are known as flowchart symbols .

The various symbols used are as follows.

Terminator Symbol For example :

The oval symbol indicates Start, Stop and
Start
Halt in a program’s logic flow. A pause/halt

is generally used in a program logic under

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