The calculation of Hamiltonian Circuits is an NP-complete task. This paper uses slightly modified complete sets of Hamiltonian circuits for the classification of documents. The solution method is based on a SAT-instance with a huge number of clauses which is flattening the knowledge about the problem. We suggest an even more compact model of Boolean equations that preserves the knowledge by summarizing restrictions and requirements. The presented implicit two-phase SAT-solver finds efficiently the solution using operations of the XBOOLE library. This solver can be included easily as signal processing unit into the device where the classification of the documents is required.