Imagine you are creating a digital wallet application. You need to create a DigitalWallet class that represents a user’s wallet where they can store money.

1. Define access modifiers for the class fields:

   • balance should be private to prevent direct modification from outside the class.
   • owner should be protected to allow access in potential subclasses.
   • Methods like addMoney and showBalance should be public so that external code can safely interact with the wallet.

2. Implement a constructor using the initializer list syntax:

   • It should take ownerName as a parameter.
   • Initialize owner with the passed ownerName.
   • Initialize balance to 0.0.

3. Implement the addMoney method:

   • Check if the amount is greater than 0.
   • If yes, add it to balance and print a message like "150$ added to Alice's wallet."
   • Otherwise, print "Invalid amount!".

4. Implement the showBalance method:

   • Print the owner’s name and the current balance in a readable format.