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Thread: Fill array concurrently

  1. #1
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    Default Fill array concurrently

    I am trying to populate an array with random numbers in parallel.

    When I build it using Eclipse I get the error: "There is an error in the required project - Threads"

    Not very helpful! I'm at a loss as to what is wrong, any help would be appreciated.

     
    public class PopulateArray extends Thread {
     
    	private int f[];
    	private int a,b;
    	private int x;
     
    	public PopulateArray(int list[],int a, int b, int x){
    		f = list; this.a = a; this.b = b; this.x = x;
    	}
     
    	@Override
    	public void run() {
    		for(int j = a; j < b; j++) {
    			f[j] = x;
    		}
     
    	}
     
    }
     
    public class ShuffleResult {
     
    	public static void main(String[] args) {
    		//Populate array
    		int list[] = new int[100];
     
    		Thread t = new PopulateArray(list, 0 , 50 , (int)Math.random()* 100);
    		Thread t1 = new PopulateArray(list, 50 , list.length , (int)Math.random()* 100);
     
    		t.start(); t1.start();
    		try{
    			t.join(); t1.join();
    		}
    		catch(InterruptedException e){ }
     
    		//Print array
    		for(int i : list){
    			System.out.print(list[i] + " ");
     
    		}
    	}
     
    }

    If i proceed with the build the output is 100 zero's so obviously PopulateArray isn't doing anything?


  2. #2
    Super Moderator helloworld922's Avatar
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    Default Re: Fill array concurrently

    Did you remember to import the threads class?

  3. #3
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    Default Re: Fill array concurrently

    Seems like it was an issue with the java project within Eclipse, I created a new package and it complies fine now!

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