//Sample_matches.java
class Sample_matches{
    public static void main(String[] args){

        String regex = "abcd";
        System.out.println(regex);
        System.out.println("----------");

        String[] strs = {
          "abcd",
          "aabcd",
          "abcde"
        };
        boolean boo;

        for(String str : strs){
          boo = str.matches(regex);
          System.out.println(str + "\t" + boo);
        }
    }
}