Cyclomatic complexity. Cyclomatic complexity of a program is a structural (or topological) measure of programs' complexity for measuring software quality. Cyclomatic complexity measuring allows you to evaluate the quality of the program code and detect high-complexity procedures. High-complexity procedures are subject to errors and detecting them is highly required to perform code review. Program cyclomatic complexity was the first topological complexity measure which was used in practice and became basis for many modifications. Measuring of cyclomatic complexity relates to static code analysis methods.