Hi , does anyone know the Donald B. Johnson's

**algorithm** which enumarates all the elementary circuits (cycles) in a Directed graph? link text
I have the paper he had published in 1975 but I cannot understand the pseudo-code. My goal is to implement this

**algorithm** in java.
Some questions i have is for example what is the matrix Ak it refers to. In the pseudo code mentions that
Ak:=adjacency structure of strong component K with least
vertex in subgraph of G induced by {s,s+1,....n};
Does that mean i have to implement another

**algorithm** that finds the Ak matrix?
Another question is what the following means?
begin logical f;
Does also the line "logical procedure CIRCUIT (integer value v);" means that the circuit procedure returns a logical variable. In the pseudo code also has the line "CIRCUIT := f;" . Does this mean?
It would be great if someone could translate this 1970's pseudocode to a more modern type of pseudo code so i can understand it
in case you are interested to help but you cannot find the paper please email me at

[email protected] and i will send you the paper.
Thanks in advance