Hackerearth-Java

When executed, your completed code should print the following:

Generic Sports
Each team has n players in Generic Sports
Soccer Class
Each team has 11 players in Soccer Class

Solution:

class Sports {
	String getName() {
		return "Generic Sports";
	}
	 // Write your overridden getNumberOfTeamMembers method here
	void getNumberOfTeamMembers() {
		System.out.println("Each team has n players in " + getName());
	}
}
class Soccer extends Sports {
	@Override
	String getName() {
		return "Soccer Class";
	}
}
public class JavaMethodOverriding {
	public static void main(String[] args) {
		Sports c1 = new Sports();
		Soccer c2 = new Soccer();
		System.out.println(c1.getName());
		c1.getNumberOfTeamMembers();
		System.out.println(c2.getName());
		c2.getNumberOfTeamMembers();
	}
}

     47. Challenge : Java Method Overriding 2

When a method in a subclass overrides a method in superclass, it is still possible to call the overridden method using superkeyword. If you write super.func() to call the function func(), it will call the method that was defined in the superclass.

You are given a partially completed code in the editor. Modify the code so that the code prints the following text:

Hello I am a motorcycle, I am a cycle with an engine.
My ancestor is a cycle who is a vehicle with pedals.

Solution:

class BiCycle {
	String define_me() {
		return "a vehicle with pedals.";
	}
}
class MotorCycle extends BiCycle {
	String define_me() {
		return "a cycle with an engine.";
	}
	MotorCycle() {
		System.out.println("Hello I am a motorcycle, I am " + define_me());
		String temp = super.define_me(); // Fix this line
		System.out.println("My ancestor is a cycle who is " + temp);
	}
}
public class JavaMethodOverriding2SuperKeyword {
	public static void main(String[] args) {
	 new MotorCycle();
	}
}

     48. Challenge : Java Instaneof Keyword

The Java instanceof operator is used to test if the object or instance is an instanceof the specified type.

In this problem we have given you three classes in the editor:

• Student class
• Rockstar class
• Hacker class

In the main method, we populated an ArrayList with several instances of these classes. count method calculates how many instances of each type is present in the ArrayList. The code prints three integers, the number of instance of Student class, the number of instance of Rockstar class, the number of instance of Hacker class.

But some lines of the code are missing, and you have to fix it by modifying only 3 lines! Don’t add, delete or modify any extra line.

To restore the original code in the editor, click on the top left icon in the editor and create a new buffer.

Sample Input

5
Student
Student
Rockstar
Student
Hacker

Sample Output

3 1 1

Solution:

class Student {
}
class Rockstar {
}
class Hacker {
}
public class JavaInstanceofkeyword {
	static String count(ArrayList mylist) {
		int a = 0, b = 0, c = 0;
		for (int i = 0; i < mylist.size(); i++) {
			Object element = mylist.get(i);
			if (element instanceof Student)
				a++;
			if (element instanceof Rockstar)
				b++;
			if (element instanceof Hacker)
				c++;
		}
		String ret = Integer.toString(a) + " " + Integer.toString(b) + " " + Integer.toString(c);
		return ret;
	}
	public static void main(String[] args) {
		ArrayList mylist = new ArrayList();
		Scanner sc = new Scanner(System.in);
		int t = sc.nextInt();
		for (int i = 0; i < t; i++) {
			String s = sc.next();
			if (s.equals("Student"))
				mylist.add(new Student());
			if (s.equals("Rockstar"))
				mylist.add(new Rockstar());
			if (s.equals("Hacker"))
				mylist.add(new Hacker());
		}
		System.out.println(count(mylist));
		sc.close();
	}
}

     49. Challenge : Java Iterator

Java Iterator class can help you to iterate through every element in a collection. Here is a simple example:

import java.util.*;
public class Example{
    public static void main(String []args){
        ArrayList mylist = new ArrayList();
        mylist.add("Hello");
        mylist.add("Java");
        mylist.add("4");
        Iterator it = mylist.iterator();
        while(it.hasNext()){
            Object element = it.next();
            System.out.println((String)element);
        }
    }
}

In this problem you need to complete a method func. The method takes an ArrayList as input. In that ArrayList there is one or more integer numbers, then there is a special string “###”, after that there are one or more other strings. A sample ArrayListmay look like this:

element[0]=>42
element[1]=>10
element[2]=>"###"
element[3]=>"Hello"
element[4]=>"Java"

You have to modify the func method by editing at most 2 lines so that the code only prints the elements after the special string “###”. For the sample above the output will be:

Hello
Java

Note: The stdin doesn’t contain the string “###”, it is added in the main method.

To restore the original code in the editor, click the top left icon on the editor and create a new buffer.

Solution:

public class JavaIterator {
	static Iterator func(ArrayList mylist) {
		Iterator it = mylist.iterator();
		while (it.hasNext()) {
			Object element = it.next();
			if (element instanceof String)// Hints: use instanceof operator
				break;
		}
		return it;
	}
	@SuppressWarnings({ "unchecked" })
	public static void main(String[] args) {
		ArrayList mylist = new ArrayList();
		Scanner sc = new Scanner(System.in);
		int n = sc.nextInt();
		int m = sc.nextInt();
		for (int i = 0; i < n; i++) {
			mylist.add(sc.nextInt());
		}
		mylist.add("###");
		for (int i = 0; i < m; i++) {
			mylist.add(sc.next());
		}
		Iterator it = func(mylist);
		while (it.hasNext()) {
			Object element = it.next();
			System.out.println((String) element);
		}
		sc.close();
	}
}

     50. Challenge : Java Exception Handling (Try-Catch)

Exception handling is the process of responding to the occurrence, during computation, of exceptions – anomalous or exceptional conditions requiring special processing – often changing the normal flow of program execution. (Wikipedia)

Java has built-in mechanism to handle exceptions. Using the try statement we can test a block of code for errors. The catchblock contains the code that says what to do if exception occurs.

This problem will test your knowledge on try-catch block.

You will be given two integers x and y as input, you have to compute x/y. If x and y are not 32 bit signed integers or if y is zero, exception will occur and you have to report it. Read sample Input/Output to know what to report in case of exceptions.

Sample Input 0:

10
3

Sample Output 0:

3

Sample Input 1:

10
Hello

Sample Output 1:

java.util.InputMismatchException

Sample Input 2:

10

Sample Output 2:

java.lang.ArithmeticException: / by zero

Sample Input 3:

23.323

Sample Output 3:

java.util.InputMismatchException

Solution:

public class JavaExceptionHandlingTryCatch {
	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		try {
			int x = sc.nextInt();
			int y = sc.nextInt();
			int z = x / y;
			System.out.println(z);
		} catch (ArithmeticException e) {
			System.out.println(e);
		} catch (InputMismatchException e) {
			System.out.println(e.getClass().getName());
		} finally {
			sc.close();
		}
	}
}

     51. Challenge : Java Varargs – Simple Addition

1
2
3
4
5
6

1+2=3
1+2+3=6
1+2+3+4+5=15
1+2+3+4+5+6=21

public class JavaVarargsSimpleAddition {
	public void add(int... a) {
		String b = "";
		int c = 0;
		for (int i : a) {
			b += i + "+";
			c += i;
		}
		System.out.print(b.substring(0, b.length() - 1));
		System.out.println("=" + c);
	}
}

class Student{
    private String name;
    private String id;
    private String email;
    public String getName() {
        return name;
    }
    public void setId(String id) {
        this.id = id;
    }
    public void setEmail(String email) {
        this.email = email;
    }
    public void anothermethod(){  }
    ......
    ......
    some more methods
    ......
}

anothermethod
getName
setEmail
setId
......
......
some more methods
......

class Student {
	private String name;
	private String id;
	private String email;
	public String getName() {
		return name;
	}
	public void setId(String id) {
		this.id = id;
	}
	public void setEmail(String email) {
		this.email = email;
	}
	public void anothermethod() {
	}
}
public class JavaReflectionAttributes {
	public static void main(String[] args) {
		Class student = new Student().getClass();
		Method[] methods = student.getDeclaredMethods();
		ArrayList<String> methodList = new ArrayList<>();
		for (Method m : methods) {
			methodList.add(m.getName());
		}
		Collections.sort(methodList);
		for (String name : methodList) {
			System.out.println(name);
		}
	}
}

8

8 is power of 2
An instance of class: Solution.Inner.Private has been created

public class CanYouAccess {
	public static void main(String[] args) throws Exception {
		DoNotTerminate.forbidExit();
		try {
			BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
			int num = Integer.parseInt(br.readLine().trim());
			Object o;// Must be used to hold the reference of the instance of the class
						// Solution.Inner.Private
			// Inner i= new Inner();
			// Private p=new Private();
			/**main code starts from here*/
			CanYouAccess.Inner si = new CanYouAccess.Inner();
			o = si.new Private();
			System.out.println(num + " is " + ((CanYouAccess.Inner.Private) o).powerof2(num));
			/**main code end  here*/
			System.out.println("An instance of class: " + o.getClass().getCanonicalName() + " has been created");
		} // end of try
		catch (DoNotTerminate.ExitTrappedException e) {
			System.out.println("Unsuccessful Termination!!");
		}
	}// end of main
	static class Inner {
		private class Private {
			private String powerof2(int num) {
				return ((num & num - 1) == 0) ? "power of 2" : "not a power of 2";
			}
		}
	}// end of Inner
}// end of Solution
class DoNotTerminate { // This class prevents exit(0)
	public static class ExitTrappedException extends SecurityException {
		private static final long serialVersionUID = 1L;
	}
	public static void forbidExit() {
		final SecurityManager securityManager = new SecurityManager() {
			@Override
			public void checkPermission(Permission permission) {
				if (permission.getName().contains("exitVM")) {
					throw new ExitTrappedException();
				}
			}
		};
		System.setSecurityManager(securityManager);
	}
}

cake

The factory returned class Cake
Someone ordered a Dessert!

pizza

The factory returned class Pizza
Someone ordered Fast Food!

interface Food {
	public String getType();
}
class Pizza implements Food {
	public String getType() {
		return "Someone ordered a Fast Food!";
	}
}
class Cake implements Food {
	public String getType() {
		return "Someone ordered a Dessert!";
	}
}
class FoodFactory {
	public Food getFood(String order) {
		/**
		 * main code starts from here
		 */
		if (order.equalsIgnoreCase("Pizza")) {
			return new Pizza();
		} else if (order.equalsIgnoreCase("Cake")) {
			return new Cake();
		}
		return null;
		/** main code end herer */
	}// End of getFood method
}// End of factory class
public class JavaFactoryPattern {
	public static void main(String args[]) {
		Do_Not_Terminate.forbidExit();
		Scanner sc = null;
		try {
			sc = new Scanner(System.in);
			// creating the factory
			FoodFactory foodFactory = new FoodFactory();
			// factory instantiates an object
			Food food = foodFactory.getFood(sc.nextLine());
			System.out.println("The factory returned " + food.getClass());
			System.out.println(food.getType());
		} catch (Do_Not_Terminate.ExitTrappedException e) {
			System.out.println("Unsuccessful Termination!!");
		} finally {
			sc.close();
		}
	}
}
class Do_Not_Terminate {
	public static class ExitTrappedException extends SecurityException {
		private static final long serialVersionUID = 1L;
	}
	public static void forbidExit() {
		final SecurityManager securityManager = new SecurityManager() {
			@Override
			public void checkPermission(Permission permission) {
				if (permission.getName().contains("exitVM")) {
					throw new ExitTrappedException();
				}
			}
		};
		System.setSecurityManager(securityManager);
	}
}

hello world

Hello I am a singleton! Let me say hello world to you

public class JavaSingletonPattern {
	public String str = "";
	private static final JavaSingletonPattern instance=null;
	private JavaSingletonPattern() {
	}
	public static JavaSingletonPattern getSingleInstance() {
		if (instance == null)
			return new JavaSingletonPattern();
		return instance;
	}
}

AndhraPradesh

Lily

public class CovariantReturnTypes {
/**
 * main code starts from here** */
	class Flower{
	    public String whatsYourName(){
	        return "I have many names and types.";
	    }
	}
	class Jasmine extends Flower{
	    public String whatsYourName(){
	        return "Jasmine";
	    }
	}
	class Lily extends Flower{
	    public String whatsYourName(){
	        return "Lily";
	    }
	}
	class Lotus extends Flower{
	    public String whatsYourName(){
	        return "Lotus";
	    }
	}
	class State{
	    Flower yourNationalFlower(){
	        return new Flower();
	    }
	}
	class WestBengal extends State{
	    Jasmine yourNationalFlower(){
	        return new Jasmine();
	    }
	}
	class Karnataka extends State{
	    Lotus yourNationalFlower(){
	        return new Lotus();
	    }
	}
	class AndhraPradesh extends State{
	    Lily yourNationalFlower(){
	        return new Lily();
	    }
	    /**
	     * main code ends here  */
	}
}

  BufferedReader br=new BufferedReader(new InputStreamReader(in));

2
1
3
4
5

2
2
2 3
2 3 5 

public class PrimeChecker {
	public void checkPrime(int... num) {
		String str = "";
		for (int n : num) {
			boolean found = true;
			if (n <= 3 && n > 1) {
				str += n + " ";
			} else {
				for (int i = 2; i <= Math.sqrt(n); i++) {
					if (n % i == 0) {
						found = false;
						break;
					}
				}
				if (found && n != 1) {
					str += n + " ";
				}
			}
		}
		System.out.println(str);
	}
}

@Entity
Class DemoClass{
}

@Entity(EntityName="DemoClass")
Class DemoClass{
}

@Target(ElementType.METHOD)
@Retention(RetentionPolicy.RUNTIME)
@interface FamilyBudget {
   String userRole() default "GUEST";
}

@Target(ElementType.METHOD)
@Retention(RetentionPolicy.RUNTIME)
@interface FamilyBudget {
    String userRole() default "GUEST";
}
class FamilyMember {
    public void seniorMember(int budget, int moneySpend) {
        System.out.println("Senior Member");
        System.out.println("Spend: " + moneySpend);
        System.out.println("Budget Left: " + (budget - moneySpend));
    }
    public void juniorUser(int budget, int moneySpend) {
        System.out.println("Junior Member");
        System.out.println("Spend: " + moneySpend);
        System.out.println("Budget Left: " + (budget - moneySpend));
    }
}
public class Solution {
    public static void main(String[] args) {
        Scanner in = new Scanner(System.in);
        int testCases = Integer.parseInt(in.nextLine());
        while (testCases > 0) {
            String role = in.next();
            int spend = in.nextInt();
            try {
                Class annotatedClass = FamilyMember.class;
                Method[] methods = annotatedClass.getMethods();
                for (Method method : methods) {
                    if (method.isAnnotationPresent(FamilyBudget.class)) {
                        FamilyBudget family = method
                                .getAnnotation(FamilyBudget.class);
                        String userRole = family.userRole();
                        int budgetLimit = family.budgetLimit();
                        if (userRole.equals(role)) {
                            if(spend<=budgetLimit){
                                method.invoke(FamilyMember.class.newInstance(),
                                        budgetLimit, spend);
                            }else{
                                System.out.println("Budget Limit Over");
                            }
                        }
                    }
                }
            } catch (Exception e) {
                e.printStackTrace();
            }
            testCases--;
        }
    }
}

UserRole MoneySpend

3
SENIOR 75
JUNIOR 45
SENIOR 40

Senior Member
Spend: 75
Budget Left: 25
Junior Member
Spend: 45
Budget Left: 5
Senior Member
Spend: 40
Budget Left: 60

@Target(ElementType.METHOD)
@Retention(RetentionPolicy.RUNTIME)
@interface FamilyBudget {
	String userRole() default "GUEST";
	int moneySpend() default 100;
}
class FamilyMember {
	@FamilyBudget(userRole = "SENIOR")
	public void seniorMember(int budget, int moneySpend) {
		System.out.println("Senior Member");
		System.out.println("Spend: " + moneySpend);
		System.out.println("Budget Left: " + (budget - moneySpend));
	}
	@FamilyBudget(userRole = "JUNIOR", moneySpend = 50)
	public void juniorUser(int budget, int moneySpend) {
		System.out.println("Junior Member");
		System.out.println("Spend: " + moneySpend);
		System.out.println("Budget Left: " + (budget - moneySpend));
	}
}
public class JavaAnnotations {
	public static void main(String[] args) {
		Scanner in = new Scanner(System.in);
		int testCases = Integer.parseInt(in.nextLine());
		while (testCases > 0) {
			String role = in.next();
			int spend = in.nextInt();
			try {
				Class annotatedClass = FamilyMember.class;
				Method[] methods = annotatedClass.getMethods();
				for (Method method : methods) {
					if (method.isAnnotationPresent(FamilyBudget.class)) {
						FamilyBudget family = method.getAnnotation(FamilyBudget.class);
						String userRole = family.userRole();
						int budgetLimit = family.moneySpend();
						if (userRole.equals(role)) {
							if (budgetLimit >= spend) {
								method.invoke(FamilyMember.class.newInstance(), budgetLimit, spend);
							} else {
								System.out.println("Budget Limit Over");
							}
						}
					}
				}
			} catch (Exception e) {
				e.printStackTrace();
			}
			testCases--;
		}
		in.close();
	}
}

5
1 4
2 5
3 898
1 3
2 12

EVEN
PRIME
PALINDROME
ODD
COMPOSITE

interface PerformOperation {
	boolean check(int a);
}
class MyMath {
	public static boolean checker(PerformOperation p, int num) {
		return p.check(num);
	}
	// Write your code here
	public static PerformOperation isOdd() {
		return n -> ((n & 1) == 1);
	}
	public static PerformOperation isPrime() {
		return n -> {
			if (n < 2) {
				return false;
			} else {
				int k = (int) Math.sqrt(n);
				for (int i = 2; i <= k; i++) {
					if (n % i == 0)
						return false;
				}
				return true;
			}
		};
	}
	public static PerformOperation isPalindrome() {
		return n -> {
			String org = n + "";
			String newString = new StringBuffer(org).reverse().toString();
			return org.equals(newString);
		};
	}
}
public class JavaLambdaExpressions {
	public static void main(String[] args) throws IOException {
		MyMath ob = new MyMath();
		BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
		int T = Integer.parseInt(br.readLine());
		PerformOperation op;
		boolean ret = false;
		String ans = null;
		while (T-- > 0) {
			String s = br.readLine().trim();
			StringTokenizer st = new StringTokenizer(s);
			int ch = Integer.parseInt(st.nextToken());
			int num = Integer.parseInt(st.nextToken());
			if (ch == 1) {
				op = ob.isOdd();
				ret = ob.checker(op, num);
				ans = (ret) ? "ODD" : "EVEN";
			} else if (ch == 2) {
				op = ob.isPrime();
				ret = ob.checker(op, num);
				ans = (ret) ? "PRIME" : "COMPOSITE";
			} else if (ch == 3) {
				op = ob.isPalindrome();
				ret = ob.checker(op, num);
				ans = (ret) ? "PALINDROME" : "NOT PALINDROME";
			}
			System.out.println(ans);
		}
	}
}

HelloWorld

68e109f0f40ca72a15e05cc22786f8e6

Javarmi123

2da2d1e0ce7b4951a858ed2d547ef485

public class JavaMD5 {
	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		String s = sc.next();
		System.out.println(getMD5(s));
		sc.close();
	}
	private static String getMD5(String s) {
		StringBuffer sb = new StringBuffer();
		try {
			MessageDigest md = MessageDigest.getInstance("MD5");
			byte[] result = md.digest(s.getBytes());
			for (int i = 0; i < result.length; i++) {
				String hex = Integer.toHexString(0xff & result[i]);
				if (hex.length() == 1)
					sb.append('0');
				sb.append(hex);
			}
		} catch (NoSuchAlgorithmException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
		return sb.toString();
	}
}

HelloWorld

872e4e50ce9990d8b041330c47c9ddd11bec6b503ae9386a99da8584e9bb12c4

Javarmi123

f1d5f8d75bb55c777207c251d07d9091dc10fe7d6682db869106aacb4b7df678

public class JavaSHA256 {
	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		String s = sc.next();
		System.out.println(getSHAHEX(s));
		sc.close();
	}
	private static String getSHAHEX(String s) {
		StringBuffer sb = new StringBuffer();
		try {
			MessageDigest digest = MessageDigest.getInstance("SHA-256");
			byte[] result = digest.digest(s.getBytes());
			for (int i = 0; i < result.length; i++) {
				String hex = Integer.toHexString(0xff & result[i]);
				if (hex.length() == 1)
					sb.append('0');
				sb.append(hex);
			}
		} catch (NoSuchAlgorithmException e) {
			e.printStackTrace();
		}
		return sb.toString();
	}
}

5
4 7 2 5 12
0 1 0 0 1
1 2
1 3
3 4
3 5

24
40
15

enum Color {
	RED, GREEN
}
abstract class Tree {
	private int value;
	private Color color;
	private int depth;
	public Tree(int value, Color color, int depth) {
		this.value = value;
		this.color = color;
		this.depth = depth;
	}
	public int getValue() {
		return value;
	}
	public Color getColor() {
		return color;
	}
	public int getDepth() {
		return depth;
	}
	public abstract void accept(TreeVis visitor);
}
class TreeNode extends Tree {
	private ArrayList<Tree> children = new ArrayList<>();
	public TreeNode(int value, Color color, int depth) {
		super(value, color, depth);
	}
	public void accept(TreeVis visitor) {
		visitor.visitNode(this);
		for (Tree child : children) {
			child.accept(visitor);
		}
	}
	public void addChild(Tree child) {
		children.add(child);
	}
}
class TreeLeaf extends Tree {
	public TreeLeaf(int value, Color color, int depth) {
		super(value, color, depth);
	}
	public void accept(TreeVis visitor) {
		visitor.visitLeaf(this);
	}
}
abstract class TreeVis {
	public abstract int getResult();
	public abstract void visitNode(TreeNode node);
	public abstract void visitLeaf(TreeLeaf leaf);
}
class SumInLeavesVisitor extends TreeVis {
	private int result = 0;
	public int getResult() {
		return result;
	}
	public void visitNode(TreeNode node) {
		// do nothing
	}
	public void visitLeaf(TreeLeaf leaf) {
		result += leaf.getValue();
	}
}
class ProductOfRedNodesVisitor extends TreeVis {
	private long result = 1;
	private final int M = 1000000007;
	public int getResult() {
		return (int) result;
	}
	public void visitNode(TreeNode node) {
		if (node.getColor() == Color.RED) {
			result = (result * node.getValue()) % M;
		}
	}
	public void visitLeaf(TreeLeaf leaf) {
		if (leaf.getColor() == Color.RED) {
			result = (result * leaf.getValue()) % M;
		}
	}
}
class FancyVisitor extends TreeVis {
	private int nonLeafEvenDepthSum = 0;
	private int greenLeavesSum = 0;
	public int getResult() {
		return Math.abs(nonLeafEvenDepthSum - greenLeavesSum);
	}
	public void visitNode(TreeNode node) {
		if (node.getDepth() % 2 == 0) {
			nonLeafEvenDepthSum += node.getValue();
		}
	}
	public void visitLeaf(TreeLeaf leaf) {
		if (leaf.getColor() == Color.GREEN) {
			greenLeavesSum += leaf.getValue();
		}
	}
}
public class JavaVisitorPattern {
	static int[] values;
	static Color[] colors;
	static ArrayList<Integer>[] edges;
	// each edges[i] holds arrayList of all nodes connnected to node i
	@SuppressWarnings("unchecked")
	public static Tree solve() {
		int n;
		TreeNode root;
		Scanner sc = new Scanner(System.in);
		n = sc.nextInt();
		values = new int[n];
		colors = new Color[n];
		for (int i = 0; i < n; i++)
			values[i] = sc.nextInt();
		for (int i = 0; i < n; i++)
			colors[i] = sc.nextInt() == 0 ? Color.RED : Color.GREEN;
		// initialize arraylists
		edges = (ArrayList<Integer>[]) new ArrayList[n + 1];
		for (int i = 1; i <= n; i++)
			edges[i] = new ArrayList<Integer>();
		// read the n- 1 edges and store them in both directions
		for (int i = 0; i < n - 1; i++) {
			int edgeNode1 = sc.nextInt();
			int edgeNode2 = sc.nextInt();
			edges[edgeNode1].add(edgeNode2);
			edges[edgeNode2].add(edgeNode1);
		}
		sc.close();
		root = new TreeNode(values[0], colors[0], 0); // root is always internal
		addChildren(root, 1);
		return root;
	}
	public static void addChildren(Tree node, Integer nodeNumber) {
		// for all edges coming out of this node
		for (Integer otherNodeNumber : edges[nodeNumber]) {
			Tree otherNode;
			if (edges[otherNodeNumber].size() > 1)
				// new internal node
				otherNode = new TreeNode(values[otherNodeNumber - 1], colors[otherNodeNumber - 1], node.getDepth() + 1);
			else
				// new leaf
				otherNode = new TreeLeaf(values[otherNodeNumber - 1], colors[otherNodeNumber - 1], node.getDepth() + 1);
			((TreeNode) node).addChild(otherNode);
			edges[otherNodeNumber].remove(nodeNumber); // remove reverse edge
			if (otherNode instanceof TreeNode)
				addChildren(otherNode, otherNodeNumber);
		}
	}
	public static void main(String[] args) {
		Tree root = solve();
		SumInLeavesVisitor vis1 = new SumInLeavesVisitor();
		ProductOfRedNodesVisitor vis2 = new ProductOfRedNodesVisitor();
		FancyVisitor vis3 = new FancyVisitor();
		root.accept(vis1);
		root.accept(vis2);
		root.accept(vis3);
		int res1 = vis1.getResult();
		int res2 = vis2.getResult();
		int res3 = vis3.getResult();
		System.out.println(res1);
		System.out.println(res2);
		System.out.println(res3);
	}
}