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import java.util.HashMap;

import java.util.Map;

public class Main {

public static void main(String[] args) {

/* KEY : VALUE

* "red" : "apple"

* "yellow" : "banana"

* "white" : "radish"

* "green" : "apple"

* */

Map<String, String> fruits = new HashMap<>();

fruits.put("red", "apple");

fruits.put("yellow", "banana");

fruits.put("white", "radish");

fruits.put("green", "apple");

// fruits.containsKey("red"); // returns true, if key is found

// fruits.containsValue("apple"); // returns true, if value is found

// fruits.size(); // returns the size of the MAP

// fruits.remove("red"); // Deletes the Entry whose key is "red"

// fruits.clear();

System.out.println(fruits.get("red"));

for (Map.Entry pairEntry: fruits.entrySet()) {

System.out.println(pairEntry.getKey() + " : " + pairEntry.getValue());

}

* Map: Interface

* HashMap: Class that implements interface Map

* class HashMap implements Map {

* ...

* }

* Map Properties:

* 1. They contain values based on key

* 2. They are not ordered

* 3. "KEY" should be unique

* 4. "VALUE" can be duplicate

* */