Type Redefinition Plagiarism Detection of Token-Based Comparison

The homologous software detection technology plays a very important role in the work of intellectual property protection by identifying code plagiarism. Plagiarism mainly happens as copy-and-paste of the code, replacing the name of functions or variables, reordering the sequence of the statement, type redefinition, and so on. At present, there are three homologous software detection technology methods on the market: text-based similarity detection, token-based similarity detection and syntax structure-based similarity detection. Token-based similarity detection technology can find the plagiarism of copy-and-paste of the code, replacing the name of functions or variables, reordering the sequence of the statement but type redefinition. In order to detect code plagiarism more effectively, we present a detecting algorithm based on type redefinition plagiarism in this paper. It could detect any level of simple type redefinition plagiarism, repeated type redefinition plagiarism and type redefinition with pointer plagiarism. Experiments show, the algorithm can detect type redefinition code plagiarism effectively, increasing accuracy of detection, performing well in the code comparison field.