A comment on the decomposition of flowchart schemata

A recent paper by Prather and Giulieri raises two issues. The first concerns the pre-processing of flowcharts before attempting to isolate unstructured subflowcharts, and a modification to the principle of collapsibility defined by Hecht is introduced as an aid in this regard. The second concerns the concept of dominance and the algorithms which Prather and Giulieri present for determining subflowcharts. © 1982 The British Computer Society.