Q. If a[] is an array, why does StdOut.println(a) print out a hexadecimal integer,
such as @f62373 , instead of the elements of the array?
A. Good question. It is printing out the memory address of the array, which, unfortunately,
is rarely what you want.
Q. Why are we not using the standard Java libraries for input and graphics?
A. We are using them, but we prefer to work with simpler abstract models. The Java
libraries behind StdIn and StdDraw are built for production programming, and the
libraries and their APIs are a bit unwieldy. To get an idea of what they are like, look at
the code in StdIn.java and StdDraw.java.
Q. Can my program reread data from standard input?
A. No. You only get one shot at it, in the same way that you cannot undo println().
Q. What happens if my program attempts to read after standard input is exhausted?
A. You will get an error. StdIn.isEmpty() allows you to avoid such an error by checking
whether there is more input available.
Q. What does this error message mean?
Exception in thread "main" java.lang.NoClassDefFoundError: StdIn
A. You probably forgot to put StdIn.java in your working directory.
Q. Can a static method take another static method as an argument in Java?
A. No. Good question, since many other languages do support this capability.