Letter case trickery
This file is in a downright esoteric format, consisting of hexadecimal numbers, non-hexadecimal keywords, and "Z" indicating end-of-line. Make the hexadecimal numbers lowercase.
Start file
A4E SUM 3C0Z 2B A9 NE F2Z
End file
a4e SUM 3c0Z 2b a9 NE f2Z
View Diff
1,2c1,2 < A4E SUM 3C0Z < 2B A9 NE F2Z --- > a4e SUM 3c0Z > 2b a9 NE f2Z
Solutions by @EdgarHipp:
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