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Java Java Data Structures - Retired Efficiency! Changing Course

Posted by ANDREA HEMPHILL
ANDREA HEMPHILL
14,484 Points

Help with Java Code Challenge!

Can anyone give me a hint as to what I am missing for this challenge. It asks that I return a map that lists video title, and video. Then I got an error that said "Expected 0 keys, returned 23". Shouldn't I be returning keys if the videos need titles? I am at a wall as to why this doesn't work.

Also there weren't any compiler errors, I just didn't do the challenge correctly. 

  public Map<String, Video> videosByTitle(Course course) {

  Map<String, Video> videoMap = new HashMap<>();
 List<Video> vList = course.getVideos();

    Video aVideo;


    while(!vList.isEmpty()){ //while there are still videos in the list
     aVideo = vList.remove(0); // remove the first video
      videoMap.put(aVideo.getTitle(), aVideo); // get that video's title and add it to the map, with the video. 
    }


    return videoMap;
  }

}

1 Answer

Rob Bridges
seal-mask
.a{fill-rule:evenodd;}techdegree seal-36
Rob Bridges
Full Stack JavaScript Techdegree Graduate 35,467 Points
Rob Bridges
.a{fill-rule:evenodd;}techdegree seal-36
Rob Bridges
Full Stack JavaScript Techdegree Graduate 35,467 Points

Hey there you successfully set up your VideoMap and videoList approriately.

However I think the trouble the trouble if trying to remove the video First. an easier way to do this would be for an enhanced for loop and just go through the videos. Try something like. 

for (Video video : vList) {
  VideoMap.put(video.getTitle(), video);
}

Would set you up nicely, let me know if this doesn't help.

ANDREA HEMPHILL
ANDREA HEMPHILL
14,484 Points

Thank you, that did help. I really needed to understand my error.