What is a NumberFormatException and how can I fix it?

Error Message: Exception in thread “main” java.lang.NumberFormatException: For input string: “Ace of Clubs” at java.lang.NumberFormatException.forInputString(NumberFormatException.java:65) at java.lang.Integer.parseInt(Integer.java:580) at java.lang.Integer.parseInt(Integer.java:615) at set07102.Cards.main(Cards.java:68) C:\Users\qasim\AppData\Local\NetBeans\Cache\8.1\executor-snippets\run.xml:53: Java returned: 1 means: There was an error. We try to give you as much information as possible It was an Exception in main thread. It’s called NumberFormatException and has occurred for input … Read more

Scala Unit type

An assignment expression has type Unit in Scala. That is the reason for your compiler warning. There is a nice idiom in Scala that avoids the while loop: val iterator = Iterator.continually(reader.readNext()).takeWhile(_ != null) This gives you an iterator over whatever reader.readNext returns. The continually method returns an “infinite” iterator and takeWhile takes the prefix … Read more

What’s the difference between iterating over a file with foreach or while in Perl?

For most purposes, you probably won’t notice a difference. However, foreach reads each line into a list (not an array) before going through it line by line, whereas while reads one line at a time. As foreach will use more memory and require processing time upfront, it is generally recommended to use while to iterate … Read more