Java tutorial
import java.util.ArrayDeque; import java.util.Deque; public class Main { public static void main(String[] args) { Deque<Integer> deque = new ArrayDeque<Integer>(8); deque.add(20); deque.add(30); deque.add(10); deque.add(18); System.out.println(deque); // deque contains element 10 boolean retval = deque.contains(10); if (retval == true) { System.out.println("element 10 is contained in the deque"); } else { System.out.println("element 10 is not contained in the deque"); } } }