Flow charts are one of most famous diagrams used to show programs and processes.
Sometimes flowcharts are partitioned into 4 groups :
It's not the only classification. different people have classified flowcharts differently. In this tutorial we try to explain main concepts of flowcharts using computer program flowcharts.
Computer program flowcharts are used to show control flow in a computer program. It is sometimes used to show an algorithm without writing the code. Sometimes they are used for training purposes for beginner programmers who don't know programming codes but can understand graphical symbols in flowcharts.
A picture is worth more than thousand of words. so lets look at first flowchart sample. This sample calculates sum of numbers from 1 to N.
Start : represents the start of program. usually drawn as an ellipse but sometimes rounded squares are also used.
Arrows : represent flow of control in a program. usually means going from one command to another commands.
Rectangles : Used to show computation or a specific process. for example Multiple X by 2.
Parallelogram : Used for getting input from user or sending output to user.
Rhombus : Used for conditional flow control where program has to decide which way to go. a good is example is : if X is devisable by 2 do these and if not do those. without conditional flow control, program would have just one path from start to end but with them they may be lots of different paths from start to end.
End : represents the end of program. usually drawn as an ellipse but sometimes rounded squares are also used.
A flowchart which calculates N! :
A flowchart which checks if a number is prime :
A flowchart which shows all prime numbers smaller or equal to N :
A flowchart which calculates all divisors of N :
A flowchart which checks if 3 numbers can be length of sides of a triangle :
1- Draw a flowchart that checks if a number is a member of Fibonacci sequence ?
2- Draw a flowchart that shows all Fibonacci sequence numbers that are smaller or equal to n ?
My personal experience to learn flowcharts is to look at a sample carefully , then put the sample away and try to draw the same sample on the paper.
In this tutorial we studied the concepts of flowcharts. although we used computer program flowcharts as an example but the concepts is the same in other flowchart diagrams.