## Relevant Articles
- [Object.toString() vs String.valueOf()](https://www.baeldung.com/java-object-tostring-vs-string-valueof)
- [Convert String to Int Using Encapsulation](https://www.baeldung.com/java-encapsulation-convert-string-to-int)
- [HashMap with Multiple Values for the Same Key](https://www.baeldung.com/java-hashmap-multiple-values-per-key)