A simple program that tests the correlation of accounts is especially suitable for students of business academies and business or economics high schools with accounting courses. The program reads the tested information from the data.dat file, which is located in the directory together with it and then tests them in random order. If the student being tested makes a mistake, the correct answer is also displayed. By modifying the data.dat file, each user can enter his own accounting operations into the database or modify the existing ones according to his knowledge.