import java.util.*;

sealed interface AncTree permits Unknown, Child { 
    int size();
    AncTree changeName( /* AncTree this, */ String before, String after );
    }


record Unknown() implements AncTree {

    public int size(/*Unknown this*/) { return 0; }

    public Unknown changeName( /* AncTree this, */ String before, String after ) { return this; }

    } 


record Child(String name, int yob, String eye, AncTree ma, AncTree pa) implements AncTree { 

    public int size(/*Unknown this*/) {
          return this.ma().size()
                 + 1
                 + this.pa().size();
        }

  
    public Child changeName(/*Child this,*/ String before, String after ) {
        return new Child( this.name.equals(before)  ?   after  :  this.name, 
                         this.yob(),
                         this.eye(),
                         this.ma().changeName(before,after),
                         this.pa().changeName(before,after)
                         );
        }



    }









class TestAncTree {

    static void testSize() {
        assert( unk.size() == 0 );
        assert( jackie.size() == 1 );
        assert( marge.size() == 2 );
        assert( homer.size() == 3 );
        assert( lisa.size() == 6 );
        }

    static void testChangeName() {
	assert unk.changeName( "Homer", "El Homero" ).equals( unk );
	assert jackie.changeName( "Homer", "El Homero" ).equals( jackie );
	assert marge.changeName( "Homer", "El Homero" ).equals( marge );


	assert homer.changeName( "Homer", "El Homero" ).equals( 
               new Child( "El Homero",
			  homer.yob(), 
			  homer.eye(), 
			  homer.ma().changeName( "Homer", "El Homero" ),
			  homer.pa().changeName( "Homer", "El Homero" )
			  ) );
	assert bart.changeName( "Homer", "El Homero" ).equals( 
               new Child( "Bart",
			  bart.yob(), 
			  bart.eye(), 
			  marge,
			  new Child( "El Homero",
				     homer.yob(),
				     homer.eye(),
				     mona,
				     abe )
			  ) );

	}

    static void printSome() {
        System.out.printf( "%s\n", 
                           new Child("marge", 
	    		             1956, 
	    		             "blue",
                                     new Child( "jackie",
                                                1917,
                                                "brown",
                                                new Unknown(),
                                                new Unknown() ),
                                     new Unknown() ) );

        }


    // fields of class `Test`:
    static AncTree unk = new Unknown();
    static AncTree jackie = new Child("jackie", 1917, "brown", unk, unk );
    static AncTree marge  = new Child("marge", 1956, "blue", jackie, unk );

    static AncTree abe = new Child( "Abe", 1920, "blue", unk, unk );
    static AncTree mona = new Child( "Mona", 1929, "brown", unk, unk );

    static Child   homer = new Child( "Homer", 1955, "brown", mona, abe );

    static Child   bart = new Child( "Bart", 1979, "brown", marge, homer );
    static AncTree lisa = new Child( "Lisa", 1980, "blue", marge, homer );
    static AncTree maggie = new Child( "Maggie", 1982, "brown", marge, homer );

    


    public static void main(String... __) { testAll(); }
    static boolean TEST_VERBOSE = true;
    static void testAll() { 
	confirmAssertionsEnabled();
        printSome(); 
        testSize();
        }


    static void confirmAssertionsEnabled() {
	boolean ea = true;
	try {
            assert false;
	    ea = false;  // If we made it here, assertions weren't actually enabled, in the jvm!
            }	
	catch (AssertionError err) { /* I meant for this to happen... */ }
        if (!ea) {
            String errMsg     = "Assertions not enabled; can't test.\n"
                              + "  To test, re-run jvm with `java --enableassertions …` or `java -ea …`.\n";
            String errMsgTips = "  (I recommend *always* running with `java -ea …`.)\n"
                              + "  (I also recommend using jUnit instead of raw `assert`s, for testing !-)\n";
            throw new AssertionError(errMsg + errMsgTips);
            }
        if (TEST_VERBOSE) { System.out.println( "Assertions enabled." ); }
        }




    }