I used the ICU packages when I needed to do something like this but it's been a decade since I coded in C++. https://unicode-org.github.io/icu/userguide/dateti

I used the ICU packages when I needed to do something like this but it's been a decade since I coded in C++. https://unicode-org.github.io/icu/userguide/datetime/ https://unicode-org.github.io/icu/userguide/datetime/