HashSet usage with int arrays

Question

As I have an ArrayList of int arrays which contains duplicates, I\'d like to use HashSet. Unfortunately, I can\'t manage to use HashSet as I wish:

System.out         


        

Answer 1

Add each number individually. Don't add Arrays to HashSet

    int[] arr1 = {1,2,3};
    int[] arr2 = {1,2,3};
    System.out.println(arr1==arr2);//false
    System.out.println(arr1.equals(arr2)); //false

Two arrays with same values need not be equal (they use default equals() method defined in Object which compares references.)