import java.util.ArrayList;
public class Main {
public static void main(String[] args) {
ArrayList arrayList = new ArrayList();
arrayList.add("2");
arrayList.add("2");
arrayList.add("3");
arrayList.add("4");
arrayList.add("5");
arrayList.add("1");
arrayList.add("2");
System.out.println(arrayList.contains("2"));
int index = arrayList.indexOf("4");
if (index == -1)
System.out.println("not contain 4");
else
System.out.println("4 at index :" + index);
int lastIndex = arrayList.lastIndexOf("1");
if (lastIndex == -1)
System.out.println("not contain 1");
else
System.out.println("Last index :"+ lastIndex);
}
}
/*true
4 at index :3
Last index :5
*/