C++ Contracts has been standardized in C++26

[PotatoCP]

At Chapter 4.4, it said

algorithmica/content/english/hpc/compilation/contracts.md

Line 187 in ed1945c

Unfortunately, this exciting new feature is [not yet finally standardized](https://www.reddit.com/r/cpp/comments/cmk7ek/what_happened_to_c20_contracts/), let alone implemented in a major C++ compiler. But maybe, in a few years, we will be able to write code like this:

But lately, C++26 has https://en.cppreference.com/cpp/language/contracts