FLOWCHARTING SYMBOL TABLE

Note: In the examples below, assume that variables A and I are integer.

SYMBOL SHAPE	TYPE OF OPERATION / C Code Example	EXAMPLE OF SYMBOL USAGE
	Terminal Activity - Start, Stop or End {
	Assignment of a value to a variable, either directly or as the result of a calculation. I = I + 1;
	Softcopy - screen output to a video display. printf ("The answer is: %d", A);
	Hardcopy - document output to a printer. The C coding required to print hardcopy varies with each compiler.
	Manual Input from the Keyboard to Memory. scanf ("%d", &A);
	Decision - based on a relational condition, select from (branch to) multiple processes. if (A < 0) {statements;} else {statements;}
	Sub-routine (a.k.a. "Procedure") used to indicate a process which is defined elsewhere. INTRO (); /* Call Intro */
	Connectors: On-page (left) & Off-page (right). Used to either: Continue a flowchart at a different place either on or off the same piece of paper. Close a selection branch or loop.
	Flow of Control Arrows indicating the sequence of steps ("flow of control").
	Annotation for placing comments in logic. A = 0; /* Reset A */
	General Input/Output of Data fprintf (filename, data);

General Flowcharting Guidelines

Symbols can be drawn any size (height or width) necessary to hold the symbol's contents.
The shapes of most symbols imply the process. It is redundant to put the word "print" in a hardcopy symbol for example.
Always put an arrowhead on each line connecting symbols to indicate the "flow of control". Do not assume that is will always be down or to the right.
In output symbols, always differentiate between literal characters and identifiers by placing a box around the identifiers. For example in hardcopy output of variables named DOLLARS and CENTS mixed with some descriptive literal text, be sure to box the variable labels, like:

Also note the inclusion of the symbol ż in the example above to indicate the use of a carriage return.
The only symbols that may receive more than one incoming arrow are connectors. Never enter any other symbols using more than one arrow. If you want to do that, put a connector in front of the symbol and let the multiple arrows enter the connector.

Don't do this:

Do this:

The switch statement involves a special use of the diamond symbol. A flowchart for the following switch statement is shown to its right.

switch (ANS) {
case 'Y':
case 'y':
    X = 1;
    break;
case 'N':
case 'n':
    X =-1;
    break;
default:
    x := 0;
    break;
}

Notice that the diamond contains only the name of the single variable to be evaluated. The "legs" that exit the decision diamond are each labeled with the unique values from a limited set of possible values for the variable ANS, including the "else" (default) option.

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Last Revised: 4 October 2005	© 2005 Randolph Gibson
`www.gibson.vero-beach.fl.us/classes/cop2000/flowchart/symbols.html`	E-mail: `rgibson@ircc.edu`