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Double Trouble

Cryptography 100 pts standard
Challenge Description

The message was encoded twice, but decoding in the wrong order breaks it.

Double.txt : HA3T6ISEGZLT6TZFIZCV2SCMGFGEI43SH5NCKVBOGFHVI===

Flag format: HackCTF{...}

Files
↓ double.txt
Hints
View Hint : Hints

Hint 1: Look at the symbols. Base64 only uses / and +, but Base85 uses a much wider range of ASCII symbols like @, %, and !. Hint 2: In encoding, the "Last In, First Out" (LIFO) rule applies. The last encoding used is the first one you must decode.

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