Corruption in the C++ track repo?

Someone on Discord mentioned that the doctor-data exercise in the C++ track had corrupt files. I took a look in the repo and indeed, it looks corrupted:

cpp/exercises/concept/doctor-data/doctor_data.cpp at main · exercism/cpp (

This exercise has been added in the following PR:

feat: add concept exercise for headers by vaeng · Pull Request #741 · exercism/cpp (

I refuse to believe that the reviewers of that PR could’ve missed the corrupted data. Additionally, @vaeng did the exercise once and I reviewed his submission. I was able to find the mentoring session in my history. The file content looked OK then and it seems impossible that could’ve been missed when the exercise was started.

Since the repo contains only one commit for this file, the most likely explanation seems to be that the repository was corrupted on GitHub :scream:

EDIT: I’ve found a branch in my own fork with an old version of the file:

exercism_cpp/exercises/concept/doctor-data/doctor-data/doctor_data.cpp at feat–add-header-testing-concept · clechasseur/exercism_cpp (

The commit also exists in the official repo, although it’s no longer in any branch:

cpp/exercises/concept/doctor-data/doctor-data/doctor_data.cpp at 2ec466b281d0712b18fbb8892c8df3b6370600a1 · exercism/cpp (

@vaeng maybe you have a local copy of the repo with the correct files?

I have a copy of that repo checked out and, oddly enough, the last commit I have in my repo is that very same commit (synced Nov 12 I believe). The data looks equally mangled, though, in my copy.

Oh wow, I saw that conversation on discord as well and thought vaeng did it as a joke because the exercise is called doctor-data. Quite rare to see something like this happen in the wild

I am sorry, that this exercise confused so many of you.
The data garbage is completetly intentional and I thought it was a nice gimmick that fits the story.

At least some students did not get that as part of the story: discord discussion and GitHub issue.

I should be clearer in the introduction, that this file is exactly as it should be because it was “destroyed” and the student’s task is to recreate it.


I finished like 95% of the C++ track before you added that one so I missed out on it (One day I will finished the binary search tree, maybe). Glad to see my hunch was correct about the intentional bad data though :grin:

Didn’t capture my 12in23 and now it’s already gone, but I still got this. Thanks for all the good work there!

I feel stupid now, but am also relieved that there isn’t corruption in a GitHub repo, which would be pretty scary. Sorry for all the confusion :frowning: