Within the maintenance activity, a great deal of time is spent in the process of understanding unstructured code prior to changing or fixing the program. This involves the comprehension of complex control structures. While automated processes are available to structure entire programs, there is a need for less formal structuring processes to be used by practicing professionals on small programs or local sections of code. This paper presents methods for restructuring complex sequence, selection, and iteration structures into structured logic. The procedures are easily taught and they result in solutions of reduced complexity as compared to the original code. Whether the maintenance programmer uses these procedures simply for understanding, or for actually re-writing the program, they will,simplify efforts on unstructured code.
Colter, Mel A., "Techniques for Understanding Unstructured Code" (1985). ICIS 1985 Proceedings. 6.