// Set in Java Language
Set<
Integer
> numbers = new TreeSet<
Integer
>();
numbers.add(2);
numbers.add(5);
System.out.println(numbers); // "[2, 5]"
System.out.println(numbers.contains(7)); // "false"
System.out.println(numbers.contains(5)); // "true"
System.out.println(numbers.add(5)); // "false"
System.out.println(numbers.size()); // "2"
int sum = 0;
for (int n : numbers) { sum += n; }
System.out.println("Sum = " + sum); // "Sum = 7"
numbers.addAll(Arrays.asList(1,2,3,4,5));
System.out.println(numbers); // "[1, 2, 3, 4, 5]"
numbers.removeAll(Arrays.asList(4,5,6,7));
System.out.println(numbers); // "[1, 2, 3]"
numbers.retainAll(Arrays.asList(2,3,4,5));
System.out.println(numbers); // "[2, 3]"