Editorial for DMOJ Capture The Flag '20 G3 - Git Gud
Remember to use this editorial only when stuck, and not to copy-paste code from it. Please be respectful to the problem author and editorialist.
Submitting an official solution before solving the problem yourself is a bannable offence.
Submitting an official solution before solving the problem yourself is a bannable offence.
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The attached file is a Git repository. There are some dangling commits from deleted branches (which you can find using something like git-reflog), one of which commits two image files. Although these two image files are visibly identical, they are actually slightly different. Using a binary file differ, such as radiff2, we can find the different bytes. Concatenating these different bytes and converting to ASCII gives us the flag.
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