import java.util.TreeMap;

/*
 * Example of remove(Object key) method.
 */
public class TreeMapExample
{
    public static void main( String[] args )
    {

        TreeMap<Integer, String> treeMap = new TreeMap<Integer, String>();

        treeMap.put(1, "Cat");
        treeMap.put(2, "Dog");
        treeMap.put(4, "Apple");
        treeMap.put(3, "Ball");

        System.out.println("treeMap : " + treeMap + "\n");

        /*
         * Removes the mapping for this key from this TreeMap if present.
         * 
         * Returns: the previous value associated with key, or null if there was
         * no mapping for key. (A null return can also indicate that the map
         * previously associated null with key.)
         */

        String value = treeMap.remove(3);

        System.out.println("value : " + value + "\n");
        System.out.println("treeMap : " + treeMap + "\n");

    }
}