# EASYCTF - Diff
> description: Sometimes, the differences matter. Especially between the files in this archive.
> category: Forensics
We have 4 binaries, and according to the title, we will have to use the `diff` command:
```xxd file > file_xxdxxd file2 > file2_xxdxxd file3 > file3_xxdxxd file4 > file4_xxd```
Now we can diff:
```diff file_xxd file2_xxd .ELF.............ELF.....e......		// -> e.........................a......		// -> a.. ............... .......s.....		// -> s.......... .........................yct... .....		// -> yct......f.........		// -> fD...............D......{........		// -> {.......................d........		// -> d.......................i........		// -> i.
diff file_xxd file3_xxd ..................f.............		// -> f..`.....|.........`.f...|.......		// -> f.....................i..........		// -> i.....................ni.........		// -> ni......................tl........		// -> tl_r..rela.dyn..re _r..rey_.dyn..re 		// -> ????......................an_.......		// -> an_.
diff file_xxd file4_xxd ................ez.._problem!}..		// -> ez_problem!}```
We have this : `easyctf{diffinitl????an_ez_problem!}`
On the diff between file and file3, we can easily find the correct keys: `easyctf{diffinitly_an_ez_problem!}`