Java Collections - MAP

  A) HASHMAP

 Write a program using hashmap and store the student data , key is roll no 1,2,3, etc and value is name of student a,b,c and access  the name of roll -no = 2 .

import java.util.HashMap;

public class basichashmap {

    public static void main(String[ ] args) {

        HashMap<Integer, String> student = new HashMap<Integer,String >();

        student.put(1, "a");

        student.put(2, "b");

        student.put(3, "c");

        System.out.println(student.get(2));

    }

}

OUTPUT: 

b