\\"inverse\\" more hints: 1. you have 25 bytes, you work on 22 bytes and 3 bytes separately. 2. flag format = e(22bytes) + e(3bytes) 3. which means d(e(22bytes)) + d(e(3bytes)) must be the same with the binary words. (have you checked this before? ;) 4. it\\\'s base64, there is a possibility that d(x) == d(y) 5. we know you\\\'re confused!