Program flow chart is an expression tool used in what stages

Program flow chart, also known as program block diagram, is a graphical representation that uses uniformly specified standard symbols to describe the specific steps of program operation.

The design of the program block diagram is based on the processing flow chart. Through detailed analysis of the input and output data and the processing process, the main operating steps of the computer and Content is identified. The program block diagram is the most basic basis for program design, so its quality is directly related to the quality of program design. (Recommended study: web front-end video tutorial)

This kind of flow chart focuses on the logic and processing sequence of the program, and specifically describes the logic and steps of computer problem-solving. When there are many loop statements and transfer statements in a program, the structure of the program will be more complex, making program design and reading difficult.

The program flow chart draws the flow of the program in the form of a diagram. It is a graphical representation of the algorithm, which is intuitive, clear, and easier to understand.

The program flow chart consists of processing boxes, judgment boxes, start and end boxes, connection points, flow lines, comment boxes, etc., combined with corresponding algorithms, to form the entire program flow chart.

The processing box has a processing function; the judgment box (diamond box) has a conditional judgment function, with one entrance and two exits; the start and end boxes represent the beginning or end of the program; the connection points can connect the process lines; the process Line (indicates the path and direction of the process; the comment box is to provide necessary supplementary instructions for the operation of certain boxes in the flow chart.

Any complex algorithm can be made by sequential structure, selection ( Branch) structure and loop structure are composed of three basic structures. Therefore, when constructing an algorithm, only these three basic structures are used as "building units" and the specifications of the three basic structures are followed. They can be juxtaposed and included with each other, but they are not allowed to cross, and they are not allowed to go directly from one structure to the inside of another structure.

Because the entire algorithm is composed of three basic structures, just like using The modules are built the same, so the structure is clear, easy to verify correctness, and easy to correct errors. This method is a structured method. Programming that follows this method is structured programming. Correspondingly, as long as three basic Using the method of drawing structural flow charts, you can draw the flow chart of any algorithm.

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