Necessity of pakage in java .

Question

Is refering package is necessary in a java program ,
so why don't we see any package in challenge or competetive programming ?

Answer 1

This may help

https://beginnersbook.com/2013/03/packages-in-java/

Answer 2

Sololearn does not support package creation, it causes error in SoloLearn, but it is legal in Java, some others online Java IDEs consider it necessary to use a package. Java is not required it.

Answer 3

Thank you so much