Factor-control-flow-graph --- фактор-уграф.
Let be a set of alts of a cf-graph such that every node of belongs to a single alt from , i.e. forms a partition of .
The cf-graph in which is said to be obtained by reduction of alts into nodes (notation ) if the following properties hold:
(1) for any , if and only if there are and such that ,
(2) is the initial node of if and only if contains the initial node of ,
(3) is the terminal node of if and only if contains the terminal node of .
The cf-graph is called a factor-control-flow-graph (or factor-cf-graph) of the cf-graph with respect to .
Let be a set of mutually disjoint alts of a cf-graph that form a partitation of some subset . Then is defined as cf-graph , where .