package within another java
// A package inside another package is known as sub package.
// For example If I create a package inside letmecalculate package
// then that will be called sub package.
// Lets say I have created another package inside letmecalculate
// and the sub package name is multiply.
// So if I create a class in this subpackage it should have this package
// declaration in the beginning:
package letmecalculate.multiply;