Java For Python Programmers Edition 2

In Python, many classes are available by default. However, in Java, you must explicitly import most classes from external packages that you want to use.

You may notice that this error message looks similar to the previous one, however, it has an entirely different cause. In Java, classes like Scanner that are part of external packages (like java.util) must be explicitly imported into your source file. Java does not automatically recognize these classes. To resolve this error, you need to add an import statement for the Scanner class at the beginning of your Histo.java file, typically import java.util.Scanner;.