Source code management system for E-learning based programming education

Content based data retrieval technology is well-known in the information retrieval area. It assumes that the subject data is unstructured, but sometimes this data can be structured. This is true for computer programs. In this paper, we have proposed a canonical form of program source codes, which explicitly reveal the program structure explicitly As an application of the canonical form, the program similarity can be computed with an additional technique named local alignment, which has previously been proposed in computational biology. We have implemented a source code management system based on this method as a subsystem of the E-learning system called ESPA, supporting the evaluation of programs submitted in programming courses. We have compared the effectiveness of our method with JPlag, one of the most stable tool plagiarism detection tools currently being used.