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An introduction to flowcharting including the demonstration of functions and various control structures.

Flowcharting symbols

Terminal

The rounded rectangles, or terminal points, indicate the flowchart's starting and ending points.

Process

The rectangle depicts a process such as a mathematical computation, or a variable assignment.

Note: the C++ language equivalent is the statement.

Input/output

The parallelograms designate input or output operations.

Note: the C++ language equivalent is cin or cout.

Connectors

Sometimes a flowchart is broken into two or more smaller flowcharts. This is usually done when a flowchart does not fit on a single page, or must be divided into sections. A connector symbol, which is a small circle with a letter or number inside it, allows you to connect two flowcharts on the same page. A connector symbol that looks like a pocket on a shirt, allows you to connect to a flowchart on a different page.

On-Page Connector

Off-Page Connector

Decision

The diamond is used to represent the true/false statement being tested in a decision symbol.

Module call

A program module is represented in a flowchart by rectangle with some lines to distinguish it from process symbol. Often programmers will make a distinction between program control and specific task modules as shown below.

Note: C++ equivalent is the function.

Local module: usually a program control function.

Library module: usually a specific task function.

Flow lines

Note: The default flow is left to right and top to bottom (the same way you read English). To save time arrowheads are often only drawn when the flow lines go contrary the normal.

Examples

We will demonstrate various flowcharting items by showing the flowchart for some pseudocode.

Functions

Pseudocode: function with no parameter passing

Function clear monitor Pass In: nothing Direct the operating system to clear the monitorPass Out: nothing Endfunction

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Function clear monitor

Pseudocode: function main calling the clear monitor function

Function main Pass In: nothingDoing some lines of code Call: clear monitorDoing some lines of code Pass Out: value zero to the operating systemEndfunction

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Function main

Sequence control structures

The next item is pseudocode for a simple temperature conversion program. This demonstrates the use of both the on-page and off-page connectors. It also illustrates the sequence control structure where nothing unusually happens. Just do one instruction after another in the sequence listed.

Pseudocode: sequence control structure

Filename: Solution_Lab_04_Pseudocode.txt Purpose: Convert Temperature from Fahrenheit to CelsiusAuthor: Ken Busbee; © 2008 Kenneth Leroy Busbee Date: Dec 24, 2008Pseudocode = IPO Outline inputdisplay a message asking user for the temperature in Fahrenheit get the temperature from the keyboardprocessing calculate the Celsius by subtracting 32 from the Fahrenheittemperature then multiply the result by 5 then divide the result by 9. Round up or down to the whole number.HINT: Use 32.0 when subtracting to ensure floating-point accuracy. outputdisplay the celsius with an appropriate message pause so the user can see the answer

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Sequence control structure

Sequence control structured continued

Selection control structures

Pseudocode: if then else

If age>17 Display a message indicating you can vote.Else Display a message indicating you can't vote.Endif

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If then Else control structure

Pseudocode: case

Case of age 0 to 17 Display "You can't vote."18 to 64 Display "Your in your working years." 65 + Display "You should be retired."Endcase

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Case control structure

Iteration (repetition) control structures

Pseudocode: while

count assigned zero While count<5 Display "I love computers!"Increment count Endwhile

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While control structure

Pseudocode: for

For x starts at 0, x<5, increment x Display "Are we having fun?"Endfor

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The for loop does not have a standard flowcharting method and you will find it done in different ways. The for loop as a counting loop can be flowcharted similar to the while loop as a counting loop.

For control structure

Pseudocode: do while

count assigned five DoDisplay "Blast off is soon!" Decrement countWhile count>zero

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Do While control structure

Pseudocode: repeat until

count assigned five RepeatDisplay "Blast off is soon!" Decrement countUntil count<one

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Repeat Until control structure

Definitions

flowcharting
A programming design tool that uses graphical elements to visually depict the flow of logic within a function.
process symbol
A rectangle used in flowcharting for normal processes such as assignment.
input/output symbol
A parallelogram used in flowcharting for input/output interactions.
decision symbol
A diamond used in flowcharting for asking a question and making a decision.
flow lines
Lines (sometimes with arrows) that connect the various flowcharting symbols.

Questions & Answers

A golfer on a fairway is 70 m away from the green, which sits below the level of the fairway by 20 m. If the golfer hits the ball at an angle of 40° with an initial speed of 20 m/s, how close to the green does she come?
Aislinn Reply
cm
tijani
what is titration
John Reply
what is physics
Siyaka Reply
A mouse of mass 200 g falls 100 m down a vertical mine shaft and lands at the bottom with a speed of 8.0 m/s. During its fall, how much work is done on the mouse by air resistance
Jude Reply
Can you compute that for me. Ty
Jude
what is the dimension formula of energy?
David Reply
what is viscosity?
David
what is inorganic
emma Reply
what is chemistry
Youesf Reply
what is inorganic
emma
Chemistry is a branch of science that deals with the study of matter,it composition,it structure and the changes it undergoes
Adjei
please, I'm a physics student and I need help in physics
Adjanou
chemistry could also be understood like the sexual attraction/repulsion of the male and female elements. the reaction varies depending on the energy differences of each given gender. + masculine -female.
Pedro
A ball is thrown straight up.it passes a 2.0m high window 7.50 m off the ground on it path up and takes 1.30 s to go past the window.what was the ball initial velocity
Krampah Reply
2. A sled plus passenger with total mass 50 kg is pulled 20 m across the snow (0.20) at constant velocity by a force directed 25° above the horizontal. Calculate (a) the work of the applied force, (b) the work of friction, and (c) the total work.
Sahid Reply
you have been hired as an espert witness in a court case involving an automobile accident. the accident involved car A of mass 1500kg which crashed into stationary car B of mass 1100kg. the driver of car A applied his brakes 15 m before he skidded and crashed into car B. after the collision, car A s
Samuel Reply
can someone explain to me, an ignorant high school student, why the trend of the graph doesn't follow the fact that the higher frequency a sound wave is, the more power it is, hence, making me think the phons output would follow this general trend?
Joseph Reply
Nevermind i just realied that the graph is the phons output for a person with normal hearing and not just the phons output of the sound waves power, I should read the entire thing next time
Joseph
Follow up question, does anyone know where I can find a graph that accuretly depicts the actual relative "power" output of sound over its frequency instead of just humans hearing
Joseph
"Generation of electrical energy from sound energy | IEEE Conference Publication | IEEE Xplore" ***ieeexplore.ieee.org/document/7150687?reload=true
Ryan
what's motion
Maurice Reply
what are the types of wave
Maurice
answer
Magreth
progressive wave
Magreth
hello friend how are you
Muhammad Reply
fine, how about you?
Mohammed
hi
Mujahid
A string is 3.00 m long with a mass of 5.00 g. The string is held taut with a tension of 500.00 N applied to the string. A pulse is sent down the string. How long does it take the pulse to travel the 3.00 m of the string?
yasuo Reply
Who can show me the full solution in this problem?
Reofrir Reply
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Source:  OpenStax, Programming fundamentals - a modular structured approach using c++. OpenStax CNX. Jan 10, 2013 Download for free at http://cnx.org/content/col10621/1.22
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