Question

Using any computing tool, draw all flowgraphs (for every module) and calculate the cyclomatic complexity, v(G), essential complexity, ev(G), module design complexity, iv(G), system design complexity, S0, and integration complexity, S1for the software code

Answer 1

Referring the image of control flow graph attached

cyclomatic complexity can be calculated in following way:

1)Count the number of regions. As seen in the CFG(Control flow graph) there are 11 regions which I have numbered.

2) Count the no. of predicates + 1. As seen in CFG I have shaded predicate nodes which are total 10 nodes. Hence cyclomatic complexity=10+1=11.

Therefore cyclomatic complexity=11

Essential complexity, ev, is calculated by flowgraph reduction. Flowgraph is reduced by removing decisions that conform to single-entry, single-exit constructs. In above case if(p==q) block has single entry and single exit. Hence can be reduced to single construct.

Therefore Essential complexity=1

Module design complexity is calculated by completely removing decisions and nodes that do not affect the control calls over a module’s immediate subordinates. Above graph is reduced as following:

Therefore Module design Complexity=2

Integration Complexity is given by formula S1 = (Σ iv(Gi )) - n + 1

where n is number of modules. Here we have 5 modules and respective IVs are shown in figure.

Using formula S1=(2+1+1+1+1)-5+1=2

Therefore Integration Complexity=2