With plagiarism detection in Toph, you can automatically identify similar submission pairs.
The algorithm compares the syntax trees of the source codes rather than the texts. It can identify similarities in source codes even if variable or function names have been renamed or rearranged.
This feature is available for Standard and Prestige tier contests.
Contact Toph Support if you have questions regarding plagiarism detection in Toph or want to use this feature in your contest.