# Simple CheckinA binary file was given, I used ghidra to view the source code of it. 
![simple checkin](https://themj0ln1r.github.io/assets/img/post_img/cvctf23_checkin1.png)
In main function I observed that there were two long array are assigned to some values. And when I scroll down an `XOR` operation was done between these two array elements.
```C  for (local_78 = 0; local_78 < local_7c; local_78 = local_78 + 1) {		    if ((local_68[local_78] ^ (int)(char)local_48[local_78]) != local_58[local_78]) {		      local_74 = 0;		    }	}```
So, I copied the values of those two arrays performed a simple XOR between them, it resulted the flag.
# [Original Writeup](https://themj0ln1r.github.io/posts/cryptoversectf23)