Flowchart in C Language

 

FLOW CHARTING 

Nihar Ranjan Roy

 

What is a Flowchart? •

A flowchart is a diagram that depicts the “flow” of a program.

•

The figure shown here is a flowchart for the addition of two numbers.

START  Display message “Please enter two numbers” Read two Numbers Calculate the Sum

Display Sum END Nihar Ranjan Roy

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Basic Flowchart Symbols •

Notice there are three types of symbols in i n this flowchart:  – 

rounded rectangles parallelograms a rectangle Each symbol represents a different type of operation.  – 

 – 

•

Symbol Symbol

Name ovals or rounded rectangles (terminals)

M Meaning eaning Start or end of a process

Arrows

Flow of control

parallelograms Rectangle

Input/output Processing (indicates a process such as a mathematical computation or variable assignment )

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Flow of control in flow chart START 

Please enter two numbers

Output operation

Display message “Please enter two numbers”

Read two Numbers Calculate the Sum

Display Sum END

Nihar Ranjan Roy

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Flow of control in flow chart START 

Please enter two numbers 12

Display message “Please enter two numbers”

13

Read operation

Read two Numbers Calculate the Sum

Accept the value and store them into variables Fno Sno

Display Sum END

Nihar Ranjan Roy

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Flow of control in flow chart START 

Please enter two 12

numbers 13

Display message “Please enter two numbers”

Read two Numbers

Processing /calculation Processing/calculate

Calculate the Sum

Display Sum

Sum=Fno+Sno END

Nihar Ranjan Roy

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Flow of control in flow chart START 

Please enter two 12

numbers 13

Display message “Please enter two numbers”

25

Read two Numbers Calculate the Sum

Output

Display Sum END

Nihar Ranjan Roy

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Four Flowchart Structures Sequence Decision Repetition Case

• • • •

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Sequence Structure •

•

A series of actions are performed in sequence The addition of two numbers was a sequential activity

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Decision Structure •

•

One of two possible actions is taken, depending on a condition. A new symbol, the diamond, indicates a yes/no question. If the answer to the question is yes, the flow follows one path. If the answer is no, the flow follows another path  – 

 – 

NO

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YES

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PROBLEM

Accept two numbers and find the square of

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Decision Structure •

In the flowchart segment below, the question “is x < y?” is asked. If the answer then process A is performed. If the answer is yes, then processisB no, is performed.

NO

YES

 

x < y? Square=y*y Square=x*x

If (x