Why Version 'A' Did Not Pass, But Version 'B - java help on CodeGym

I don't know what ninkampoops gave this exercise 4-stars. I just about pulled out what remains of the few hairs on my head because this one seemed so straightforward, but took an obnoxious number of attempts to pass. Mind you, there was a whole other version that I completely came up with on my own that I liked, performed exactly as it should, and still failed the last requirement. So, I went to the Community section and found similar code, applied their tweaks and it still wouldn't pass. Then, I went to the 'extreme' and just shoved everything into the scope that read and counted 'world' altogether. It looked more confusing if one were to just walk up to it, but whatever. And it passed. What the heck? Is there some nuance I was missing here? Again, version 'A' correctly counted the number of 'world' iterations. Version A

String line = null;
        while(fileReader.ready()){
            line = fileReader.readLine();
            }
String[] lineArray = line.replaceAll("[^a-zA-Z]", " ").split(" ");
        int worldCounter = 0;
            for(int i = 0; i < lineArray.length; i++) {
                if(lineArray[i].equals("world"))
                    worldCounter++;
        }
        fileReader.close();
            System.out.println(worldCounter);
    }
}

// a) for (String s : "world!world2,world3?noworld".split("\\p{Punct}")) { System.out.println(s); } // b) System.out.println("count = arrayLength - 1: " + ("smth,world!world,world3?noworld".split("\\bworld\\b").length - 1));

int count = 0; try (BufferedReader console = new BufferedReader(new InputStreamReader(System.in)); BufferedReader in = new BufferedReader(new FileReader(console.readLine()))) { // create Matcher outside the read loop and reset, that way there is no need to compile the pattern repeatedly Matcher m = Pattern.compile("\\bworld\\b").matcher(""); while (in.ready()) { m.reset(in.readLine()); while (m.find()) { count++; } } } catch (IOException e) { throw new RuntimeException(e); } System.out.println(count);

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Thomas

Level 41 , Bayreuth, Germany

24 February 2023, 14:56

That regex just does not work. An example that works smooth as butter no,world?worst!world An example where your regex removes to much no,$world,2world here there shouldn't be any output but that regex removes anything else than a-z and A-Z and leaves that: no world world looks not really good to me. It should be no $world 2world so either a) split using punct or b) you use word boundaries and split using world

another alternative is using word boundaries \\bworld\\b or looking for entire words \\w+ in conjunction with pattern matcher

the entire word alternative would have the pattern

"\\w+"

instead and the while loop would look like

while (m.find())
    if (m.group().equals("world"))
        count++;

Why Version 'A' Did Not Pass, But Version 'B' (Non-Posted) Did?