LEC03 Flowcharts

7/31/2019 LEC03 Flowcharts

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LECTURE 03

FLOWCHARTS


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Flowcharts

- Pictographic Representation ofAlgorithms


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What Is A Flowchart?

A flowchart is a diagrammatic representationthat illustrates the sequence of operations to beperformed to get the solution of a problem.

generally drawn in the early stages offormulating computer solutions

facilitate communication between programmersand business people

play a vital role in the programming of a problemand is helpful in understanding the logic ofcomplicated and lengthy problems


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Flowchart Symbols

Start or end of the program Computational steps or

processing function of a program Input or output operation

Decision making and branching

Connector or joining of two partsof program


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Flowchart Symbols

Magnetic Tape

Magnetic Disk

Off-page connector

Flow line

Annotation

Display


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Flowchart Guidelines1. In drawing a proper flowchart, all necessary

requirements should be listed out in logical order.

2. The flowchart should be clear, neat and easy to follow.There should not be any room for ambiguity in

understanding the flowchart.3. The usual direction of the flow of a procedure or

system is from left to right or top to bottom.

4. Only one flow line should come out from a processsymbol.


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Only one flow line should come out from a

process symbol.

Flowchart Guidelines


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Only one flow line should enter a decision

symbol, but two or three flow lines, one

for each possible answer, should leavethe decision symbol


Y N


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Only one flow line is used in conjunction

with terminal symbol



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Write within standard symbols briefly. As

necessary, you can use the annotation

symbol to describe data or computationalsteps more clearly.

This is top secret


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If the flowchart becomes complex, it is better touse connector symbols to reduce the numberof flow lines. Avoid the intersection of flow linesif you want to make it more effective and betterway of communication.

Ensure that the flowchart has a logical startand finish.

It is useful to test the validity of the flowchartby passing through it with a simple test data.


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Advantages Of Using

Flowcharts1. The benefits of flowcharts are as follows:

2. Communication: flowcharts are better way ofcommunicating the logic of a system to all

concerned.3. Effective analysis: with the help of flowchart,

problem can be analyzed in more effectiveway.

4. Proper documentation: program flowchartsserve as a good program documentation,which is needed for various purposes.


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Advantages Of Using

Flowcharts1. Efficient coding: the flowcharts act as a guide

or blueprint during the systems analysis andprogram development phase.

2. Proper debugging: the flowchart helps indebugging process.

3. Efficient program maintenance: themaintenance of operating program becomes

easy with the help of flowchart. It helps theprogrammer to put efforts more efficiently onthat part.


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Limitation Of Using Flowcharts Complex logic: sometimes, the program logic is quite

complicated. In that case, flowchart becomes

complex and clumsy.

Alterations and modifications: if alterations are

required the flowchart may require re-drawing

completely.

Reproduction: as the flowchart symbols cannot be

typed, reproduction of flowchart becomes a problem.

The essentials of what is done can easily be lost in

the technical details of how it is done.


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A Sample Flowchartstart

stop

sum = 0

n = 0

n = n + 1

sum = sum + n

Is n = 10?

print sum

no yes

Documents

LEC03 Flowcharts