How do I randomly fill an array in Java?

Question

I\'m writing a program that creates a 2D array from a integer n. I then have to fill the array with values from 1 to the nn array size and check to see if it is a magic

Answer 1

create a shuffled list of numbers to add to your array, something like this:

 List numbers = new ArrayList();
 for (int i=1; i<=n*n; i++) numbers.add(i);
 Collections.shuffle(numbers);

 int [][] magic = new int [n][n];

 int index = 0;
 for (int row = 0; row < magic.length; row++)
 {
    for(int col = 0; col < magic[row].length; col++)
        magic[row][col] = numbers.get(index++);
 }