The most elegant C++ code challenge

Question

Which C++ code is the most elegant you've ever seen on SoloLearn?
Here are the rules:
1. Code should be already published at SoloLearn.
2. It must be in C++.
3. It must NOT be your code.

Answer 1

I like this code:
https://code.sololearn.com/cBVsQw3izizM/?ref=app