gitignore ignore config files except sample config file

I usually keep my configuration files under a directory named config but I don’t want these config files to be tracked by git. However, I do place a sample configuration file which I wish to be tracked by git. Normally, I name these sample configuration files as config.sample.yaml or config.sample.yaml. If there is only one config directory that I work, then this problem can be easily solved by placing another .gitignore file inside config dir, but I have multiple config dirs across my project and adding .gitignore in each of those directories and managing them seems like a really irritating way to do it.

I can achieve what I want by configuring .gitignore in the root of my project directory like this.

**/config/**/*.yaml
**/config/**/*.json
!**/config/**/*.sample.yaml
!**/config/**/*.sample.json