substring, indexOf and lastIndexOf

public class Main {
    public static void main(String[] args) {
        String s = "automation";
        System.out.println(s.substring(2, 5));
        System.out.println(s.indexOf('o'));
        System.out.println(s.lastIndexOf("o"));
        System.out.println(s.charAt(s.length() - 1));
        System.out.println(s.indexOf("z"));
    }
}