Question

In java Shuffle an ArrayList without collections.shuffle.

Answer 1

public class test{
   public static void shuffleList(List<Integer> l) {
       int n = l.size();
       Random random = new Random();
       random.nextInt();
       for (int i = 0; i < n; i++) {
           int change = i + random.nextInt(n - i);
           int helper = l.get(i);
           l.set(i, l.get(change));
           l.set(change, helper);
       }
   }
   public static void main(String args[]){
       ArrayList<Integer> list = new ArrayList<Integer>();
       list.add(1);
       list.add(2);
       list.add(3);
       list.add(4);
       list.add(5);
       System.out.println("Initial list: " + list);
       shuffleList(list);
       System.out.println("Shuffled list: " + list);
   }
}

19 20e public static void main(String args) 21 23 24 25 26 27 28 29 ArrayList<Integer> list new ArrayList<Integer>); list.add (1); list.add (2); list.add(3); list.add (4); list.add (5); System.out.println("Initial list: " + list); shufflelist(list);| System.out.println("Shuffled list: "+ list); nents.ja vaSE-130] 31 1 IL Problems@ Javadoc Declaration Console 3 sterminated> CandyBar [Java Application] /usr/lib/jvm/java-7-openjdk-amd64/bin/java (03-Sep-201 Initial list: [1, 2, 3, 4, 5] Shuffled list: [2, 5, 3, 1, 4]