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3.3.2 Flowcharts
              A flowchart is a visual program design tool in which the symbols describe
              the operations to be performed. The symbols are represented in a sequence
              of steps. The steps are connected by lines or arrows which represent the
              direction of flow of the process. Like algorithm and pseudo code, it is only
              used for planning and documentation.





                                                             Definition

                    A flowchart is a pictorial representation of an algorithm using standard symbols.




              In a flowchart, each step is represented using symbols. So, before we learn how to draw a flowchart, we need to know
              about the flowchart symbols. The symbols are tabulated below:

                                     Symbol                                        Purpose

                                                             The oval-shaped start/stop  symbol  is used to represent the
                                   START/STOP                beginning/end of a flowchart.


                                                             The parallelogram-shaped input/output box represents an input
                                INPUT/OUTPUT                 operation like accepting data from the keyboard or an output
                                                             operation like displaying the result on a monitor respectively.

                                                             The rectangle-shaped process box is used to represent arithmetic
                                  PROCESS BOX                or assignment operations carried out internally.


                                                             The diamond-shaped decision box is used to check the condition.
                                    DECISION                 It has one input and two outputs representing the actions to be
                                      BOX                    taken for two outcomes true and false.


                                                             The four arrows represent the flow lines which show the direction
                                                             of the flow of the process.
                        FLOW LINES

                                                             The on-page connectors allow the flowchart to be drawn
                                                             neatly, without intersecting lines. They are used in pairs – one
                                    ON PAGE                  denoting the end of a step and the other the continuation. The
                                  CONNECTOR                  pairs are represented by an alphabet written inside the circle.



                                                             The off-page connectors are used  to join  symbols  on  another
                                    OFF PAGE                 page. These connectors are also used in pairs.
                                  CONNECTORS







                102102  Touchpad Computer Science-XII
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