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Java

Nancy Melucci
PLUS
Nancy Melucci
Courses Plus Student 35,075 Points

Initializing an array from information in a text file

I have an assignment to read from a textfile (which I can do) and compare two arrays (which I also can do) but what I cannot figure out how to do is to initialize the arrays from the text, which looks like this:

"Glover 4 Blow Grumpy Crabby Hiddleston Gamble 8 Lowe Donaldson Alexander Sears Hudson Campos Cabrera Walton"

I see the array name, the size and the elements. I have tried making arraylists and just ignoring the first and second strings (Glover 4 and Gamble 8) and just adding the names that follow.

These are supposed to be a person's name, the number of friends and the names of the friends. I think I am supposed to have the scanner read in the name of the array, the size and populate each one. And then do the comparison.

I can post the code for my arraylist version if needed.

Hope that made sense. Thanks.

Nancy M.

2 Answers

Simon Coates
Simon Coates
28,694 Points

I tried demoing going from a string to your array and got the following

class Main {
  public static void main(String[] args) {
    String x = "hello world these are words";
    String[] line = x.split(" ");
    String[] result = new String[line.length-2];
    for(int i = 2; i<line.length; i++)    {
        result[i-2] = line[i];
    }
  }
}

Apart from this Array may be able to return an arraylist using what you get back from split. Anyhow, this is just an idea. I don't use java much. You can do something similar with arraylist.

Nancy Melucci
PLUS
Nancy Melucci
Courses Plus Student 35,075 Points

Thanks for taking the time to help me. I am still not sure how to make the first token in the file be the name of the array and the second be the size. I will keep working on it. I am having a lot of trouble with tokenizing and file processing.

Simon Coates
Simon Coates
28,694 Points

I'm not even sure if dynamic variable names are possible. Is using a map an option? A map on name, where the item looked up is an array using the passed in size.