ComProg I

• Desk checking is just reading through or checking the program manually to ensure that it is free from errors and the logic works.
• Debugging means detecting, locating, and removing errors in the computer program.
• Error may be syntax errors or logic errors.
• Syntax errors can be typographical error or incorrect format of the statement used.
• Logic errors are caused by incorrect use of control structures.
• Documenting the program consists of the written descriptions of what the program is all about and how to use it.
• Program logic formulation is a step-by-step development of a solution to a given problem. This is the most difficult part of solving a problem with a computer.
• FLOWCHART consists of boxes with different shapes that contain simple statements or sentence commonly called instructions and connect together by lines. It is easy to understand because its solution is represented in a picture.
• Data - Indicates Data
• Stored Data - Indicates data stored in formats suitable for processing
• Sequential Access Storage - Indicates only sequentially accessible data such as those on magnetic tapes & cassette tapes.
• Direct Access Storage - Indicates directly accessible data, such as those on magnetic disks & floppy disks.
• Documents - Indicates data on media human beings can read
• Display - Indicates data on any medium that displays information used by human beings, such as monitor
• Loop Limit - Composed of two parts; condition for termination and loop name are written in the symbol indicating the start & the end of the loop respectively
• Terminal Symbol - This oval, which contains either the word start or the word stop, indicates the starting and stopping point in the flowchart. A flowchart can only have one starting point but it may have many possible stopping points.
• INPUT/ OUTPUT Symbol - This parallelogram is used for INPUT and OUTPUT instruction. INPUT means to enter data into a computer or to use the computer to read the available data from magnetic disk. OUTPUT means to display the result of compilation or condition of the given solution.
• Processing Symbol - This rectangle is used for ay data processing operations for which requirements of the problem are usually done here. Examples are computation of average, and assignment of the value to the variable.
• Decision Symbol - This diamond-shaped symbol contains a condition. If the condition is true, the marked path TRUE is to be followed. If the condition is false, the marked path FALSE is to be followed.
• Arrowheads/Flow lines - Arrows are used to direct the flow of the flowchart. It shows the flow of the solution.
• Connector - It is used as a continuation symbol of a flowchart. It shows the flow of the solution.
• Initialization/Preparation Symbol - It is used to initialize variables not explicitly defined in the input but a requirement in the production of the output.
• System Flowchart – indicates a flowchart for a targeted system as a whole
• Program Flowchart – is used to describe processing procedures based on detailed analysis.
• The steps that comprise a flowchart must be organize in an orderly, understandable, and clear manner so that the program that implements this flowchart is similarly in an orderly, understandable, and clear manner.
• Sequential – steps are performed in a strictly sequential manner; each step being executed exactly once. This is the simplest method of control. It is easy to develop and understand.
• Selection Structure – One of several alternative actions is selected and executed. It involves the use of decision based on the given condition. It use decision block or the diamond shaped block. Alternative action will be represented by a processing block.
• Repetition Structure – One or more steps is performed repeatedly.
• Algorithm - is a set or series of instruction for carrying a task. It is also a procedure to produce the required output from the given input.
• Algorithm - It is similar with a paragraph that expresses a single thought. It uses English language. It is also known as pseudo code.
• Pseudo code - is a mixture of language and symbols, terms and other feature commonly used one or more high-level languages.
• High-level languages are programs used by the computer.
• Symbolic names (identifiers) are used to represent quantities being processed by the algorithm.
• Indentation - is used to set off certain key blocks of instructions.
• 1960 ALGOL language developed by International Group
• 1967 BCPL developed by Martin Richard
• 1970 B language developed by Ken Thompson
• 1972 Traditional C language developed by Dennis Ritchie
• 1978 K & R C language developed by Kernighan & Dennis Ritchie
• 1989 ANSI C language developed by ANSI committee