HashMapClassWork

import java.util.HashMap;
import java.util.Map;

public class HashMapClassWork {
    public static void main(String[] args) {
        HashMap<String, Double> MyDictionary = new HashMap<String, Double>();

        MyDictionary.put("Ivan", 3.00);
        MyDictionary.put("Georgi", 4.50);
        MyDictionary.put("Dimitur", 5.50);
        MyDictionary.put("Veselin", 3.50);
        MyDictionary.put("Canislav", 4.00);
        MyDictionary.put("Nikol", 6.00);

        System.out.println("HashMap Size:" + MyDictionary.size());

        Double TsanevMark = MyDictionary.get("Canislav");
        System.out.printf("Canislav's mark: %.2f %n", TsanevMark);

        MyDictionary.remove("Canislav");
        System.out.println("Canislav removed.");

        System.out.printf("Is Canislav in the HashTable: %b %n", MyDictionary.containsKey("Canislav"));
        System.out.printf("Is Canislav in the HashTable: %b %n", MyDictionary.containsValue(6.00));

        MyDictionary.put("Nikol", 3.25);
        System.out.println("Nikol's mark changed");

        System.out.println("Students and marks: ");

        System.out.println(MyDictionary);

        for (Map.Entry<String, Double>items : MyDictionary.entrySet()) {
            if(items.getKey().equals("Dimitur")){
                System.out.printf("Mark of %s is %.2f", items.getKey(), items.getValue());
            }
            System.out.printf("Student %s has %.2f%n",items.getKey(), items.getValue());
        }

        System.out.printf("There are %d students.%n", MyDictionary.size());
        MyDictionary.clear();
        System.out.println("Students Dictionary (By hashmap) cleared.");
        System.out.printf("Is hashtable empty: %b%n", MyDictionary.isEmpty());
    }
}