The step by step solution of a problem in a picture form is known as flowchart. It is one of the most important and oldest techniques to depict an algorithm. A Flowchart facilitates the computer in following ways:
The basic flowchart symbols are:
According to use and application of the flowchart we have two types of flowcharts: system flowchart and program flowchart.
Flowchart is a graphical representation of program solving steps so that it makes clear about the program. The concept of flowchart was given by John Vonn Neuman 1945.
Types of flowchart are:
a) System Flowchart b) Program Flowchart
|System flowchart||Program flowchart|
|1. System flowchart gives complete processing mechanism and cannot be converted into program||1. Program flowchart gives the problem solving method and can be converted into program.|
|Example: Organizational structure of a college.||Example: Problem to calculate area of triangle.|
The common guidelines (properties) of flowchart are:
The flowchart should have only one start and ending points.
Flow lines shouldn't intersect each other.
Flowchart should not contain the programming language.
The flowchart should be neat and clear for the user.
Some of the symbols used in flowchart along with their meanings are listed below:
Two disadvantages of flowchart are:
Step 1 : Start
Step 2 : Read radius and store to R
Step 3 : Assign value of pie to P
Step 4 : Find area and circumference
Step 5 : Display area and circumference
Step 6 : Stop
Step 1 : Start
Step 2 : Read A, B
Step 3 : Assign A to X and B to Y
Step 4 : Divide A by B.
Step 5 : Is remainder zero? If yes, go to step 7.
Step 6 : Assign A to B and B to remainder. And go to step 4
Step 7 : Assign B to HCF
Step 8 : Multiply X and Y and divide by HCF. And assign result to LCM.
Step 9 : Display HCF and LCM
Step 10 : Stop
The basic flowchart symbols are: 1. Start and end symbols, represented as lozenges, ovals or rounded rectangles, usually containing the word "Start" or "End", or another phrase signaling the start or end of a process, such as "submit enquiry" or "receive product". 2. Arrows, showing what's called "flow of control" in computer science. An arrow coming from one symbol and ending at another symbol signifies flow passes to the symbol the arrow points to. 3. Processing steps, represented as rectangles. Examples: "Add 1 to X"; "replace identified part"; "save changes" or similar. Input/Output, represented as a parallelogram. Examples: Get X from the user; display X. 2. Conditional (or decision), represented as a diamond (rhombus). These typically contain a Yes/No question or True/False test. This symbol is unique in that it has two arrows coming out of it, usually from the bottom point and right point, one corresponding to Yes or True, and one corresponding to No or False. The arrows should always be labeled. More than two arrows can be used, but this is normally a clear indicator that a complex decision is being taken, in which case it may need to be broken-down further, or replaced with the "pre-defined process" symbol.