12 ตุลาคม 2561 เวลา 11:53 น. 6 เอุปสรร เคล็ดลับมีอยู่ ส ไล เด อ ร์ ภาษา อังกฤษ ประการ ก็คือ1.
We draw one for each possible token. It shows the decisions that must be made based on the input seen. A parse tree is a tree that represents the syntactic structure of a string according to some formal grammar. A program that produces such trees is called a parser. 01 ar occurs 5 times pic 999. 01 max pic 999 value 0.
01 i pic 999 value 0. HIPO stands for Hierarchy plus Input, Process, Output. The first part, the hierarchy, is a visual table of contents that displays the modules in a hierarchy much like the appearance of an organization chart. Warnier-Orr diagrams are a kind of hierarchical flowchart that allows us to describe the organization of data and procedures. Orr diagrams: hierarchy, sequence, repetition, and alternation.
There are also two slightly more advanced concepts that are occasionally needed: concurrency and recursion. It is simply a nested group of sets and subsets shown as a set of nested brackets. Within one level of hierarchy, the features listed are shown in the order in which they occur. Repetition is the representation of a classic “loop” in programming terms. Alternation or selection, is the traditional “decision” process whereby a determination is made to execute one process or another.
Concurrency is one of the two advanced constructs used in the methodology. It is used whenever sequence is unimportant. Recursion is the least used of the constructs. Warnier-Orr diagrams are very similar to flowcharts, but they are more like psedoucode than blocks and shapes. They are a graphical representations of solutions or algorithms. They are a key step between the understanding of the steps needed to accomplish a task and the different steps that the program will take to finish the task.