Wow, it took me a minute to figure out how his entry works. You really could read that code and assume it was correct. The resulting image is perfectly redacted

Wow, it took me a minute to figure out how his entry works. You really could read that code and assume it was correct. The resulting image is perfectly redacted visually, and the missing data is not appended or hidden elsewhere in the file. You would only discover it by inspecting the PPM image in a text editor. Very sneaky!