You will need
- stencil for drawing block diagrams;
- - mechanical pencil;
- - eraser;
- - computer with Internet access.
The beginning and the end of the algorithm are denoted by ovals. Inside them are placed, respectively, the words "Beginning" and "End". From the oval, symbolizing the beginning of the algorithm, comes one arrow down to the oval, which symbolizes the end of the algorithm, an arrow comes from above.
Steps corresponding to the actions not related to I / o, are denoted with rectangles. An example of such action - a calculation according to the formula and assign the result of a particular variable. The arrow from the previous step comes to the rectangle on top and bottom, it comes from the arrow to the next step.
To denote steps corresponding to the operations input and output, use parallelograms. Such operations are of two types: the assignment received from either the variable data and output data from a variable to a file, port, screen, printer, etc.
Branching are indicated by the diamonds. In the top corner of the diamond arrow comes from the previous step, and from its lateral angles come the arrows marked as "No" and "Yes." They come, respectively, to the steps for compliance with and observance of the conditions. The bottom corner of the diamond is left free. The condition itself (for example, equality, a strict or nonstrict) is written inside the diamond.
Rectangle, the side walls of which are double, represents the transition to the subroutine. After the subprogram was found a return statement, execution continues with the main program. Inside the rectangle indicate the name of the subroutine. Block diagrams of all the subroutines are placed in the block diagram of the main program or on separate pages.
To draw flowcharts preferred using special stencils, using a mechanical pencil. It can be erased by the eraser like a regular pencil, but do not require sharpening.
If you wish to make a flowchart in electronic form use the online application called Flowchart. If you wish, you can also learn special programming languages in which the programming process is the preparation of a block diagram. Such languages are two: the Dragon and HiAsm.