That's saying that the java.util.Scanner constructor is marked as being able to throw the exception java.io.FileNotFoundException - you either need to wrap that in a try/catch or mark your function as ...

System.out.println("1. Classify a number as positive, negative, or zero"); System.out.println("2. Print a multiplication table for a given number"); ...

Lets say you only use Scanner and Random from util, The program should scan the code base and inside each file understand what classes and methods that package is using. This is useful because with ...