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A Nassi–Shneiderman diagram (NSD) in computer programming is a graphical design representation for structured programming.〔Hans-Georg Fill (2009). ''Visualisation for Semantic Information Systems''. p.32〕 This type of diagram was developed in 1972 by Isaac Nassi and Ben Shneiderman who were both graduate students at SUNY-Stony Brook.〔''A short history of structured flowcharts (Nassi-Shneiderman Diagrams)''. Webdoc draft: May 27, 2003. ((Source ))〕 These diagrams are also called structograms,〔Rolf Isermann (1988). ''Automatic Control: Selected papers from the triennial world congress of the International Federation of Automatic Control : Munich, Federal Republic of Germany, 27–31 July 1987, Volume 10;Volume 14''. p.89〕 as they show a program's structures. == Overview == Following a top-down design, the problem at hand is reduced into smaller and smaller subproblems, until only simple statements and control flow constructs remain. Nassi–Shneiderman diagrams reflect this top-down decomposition in a straightforward way, using nested boxes to represent subproblems. Consistent with the philosophy of structured programming, Nassi–Shneiderman diagrams have no representation for a GOTO statement. Nassi–Shneiderman diagrams are only rarely used for formal programming. Their abstraction level is close to structured program code and modifications require the whole diagram to be redrawn. Nonetheless, they can be useful for sketching processes and high-level designs. Nassi–Shneiderman diagrams are (almost) isomorphic with flowcharts. Everything you can represent with a Nassi–Shneiderman diagram you can also represent with a flowchart. For flowcharts of programs, almost everything you can represent with a flowchart you can also represent with a Nassi–Shneiderman diagram. The exceptions are constructs like goto and the C programming language ''break'' and ''continue'' statements for loops. In Germany, Nassi–Shneiderman diagrams were standardised in 1985 as DIN 66261.〔Deutsches Institut für Normung e. V. (DIN): (DIN 66261: Informationsverarbeitung; Sinnbilder für Struktogramme nach Nassi-Shneiderman ).〕 They are still used in German introductions to programming, for example Böttcher and Kneißl's introduction to C,〔Böttcher, Axel; Kneißl, Franz: ''Informatik für Ingenieure: Grundlagen und Programmierung in C''. 3rd edition. München: Oldenbourg, 2012. ISBN 978-3-486-70527-0. See especially Chapter 10: "Kontrollstrukturen" (control flow).〕 Baeumle-Courth and Schmidt's introduction to C〔Baeumle-Courth, Peter; Schmidt, Torsten: ''Praktische Einführung in C''. München: Oldenbourg, 2012. ISBN 978-3-486-70799-1. See especially Chapter 6: "Kontrollstrukturen" (control flow).〕 and Kirch's introduction to C#.〔Kirch, Ulla: ''C# lernen und professionell anwenden''. Heidelberg: mitp, 2009. ISBN 978-3-8266-5915-7. See especially Chapter 5: "Schleifen und Verzweigungen" (loops and branches).〕 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Nassi–Shneiderman diagram」の詳細全文を読む スポンサード リンク
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