Style features in the programming process which can help indicate plagiarism

In the new situation, where more and more final programming assignments are performed outside the classroom, it is necessary to pay more attention to the possibilities of understanding whether a student has created the solution on their own. To do this, it is possible to use a programming environment that logs user actions. One such environment is Thonny, which also allows the programming process to be replayed. The aim of this study is to identify style features of different learners, based on solution logs of introductory programming courses, and to explore how permanent these features are and can these indicate whether learners have solved the tasks without external aids. It can be said that non-programming style features, like the order of writing brackets or quotation marks, are more permanent and can be used to detect plagiarism. However, programming style features, such as the use of variable names or increment, are very variable between courses, and students participating in introductory courses do not have an established style. They are greatly influenced by the style features of teaching materials and solutions of sample tasks. Therefore, programming style features cannot be used to automatically check if a student has solved a task on their own.