Question

import java.util.Stack;
import java.util.ArrayList;
import java.util.Scanner;

class TreeNode{
int data;
ArrayList<TreeNode> children = new ArrayList<>();
TreeNode parent = null;
  
public TreeNode(int d){
data = d;
}
  
public TreeNode addChild(int d){
TreeNode n = new TreeNode(d);
n.setParent(this);
children.add(n);
return n;
}
  
public ArrayList<TreeNode> getChildren(){
return children;
}
  
public void setParent(TreeNode p){
parent = p;
}
  
public TreeNode getParent(){
return parent;
}
}

class Main {
public static void main(String[] args)
   {
       Scanner scan = new Scanner(System.in);
       int num;
       //Create a tree
       TreeNode root = new TreeNode(scan.nextInt());
TreeNode node1 = root.addChild(scan.nextInt());
TreeNode node11 = node1.addChild(scan.nextInt());
TreeNode node12 = node1.addChild(scan.nextInt());
TreeNode node2 = root.addChild(scan.nextInt());
TreeNode node21 = node2.addChild(scan.nextInt());
TreeNode node22 = node2.addChild(scan.nextInt());
       TreeNode node211 = node21.addChild(scan.nextInt());
       int newK = scan.nextInt();
       System.out.println(""+largerK(root, newK));
   }

   
public static int largerK(TreeNode n, int k) {
       //TODO: Find the number of elements greater than k in the tree rooted in n
       //Example: if the elements in the tree are: 10, 20, 30, 40, 50, and k=25, the method should return: 3
  
      
   }

}

Answer 1

The implementation of largerK() method within the given code is given below:

package temp;

import java.util.Stack;
import java.util.ArrayList;
import java.util.Scanner;

class TreeNode{
int data;
ArrayList<TreeNode> children = new ArrayList<>();
TreeNode parent = null;
  
public TreeNode(int d){
data = d;
}
  
public TreeNode addChild(int d){
TreeNode n = new TreeNode(d);
n.setParent(this);
children.add(n);
return n;
}
  
public ArrayList<TreeNode> getChildren(){
return children;
}
  
public void setParent(TreeNode p){
parent = p;
}
  
public TreeNode getParent(){
return parent;
}
}

class Main {
public static void main(String[] args)
{
Scanner scan = new Scanner(System.in);
int num;
//Create a tree
TreeNode root = new TreeNode(scan.nextInt());
TreeNode node1 = root.addChild(scan.nextInt());
TreeNode node11 = node1.addChild(scan.nextInt());
TreeNode node12 = node1.addChild(scan.nextInt());
TreeNode node2 = root.addChild(scan.nextInt());
TreeNode node21 = node2.addChild(scan.nextInt());
TreeNode node22 = node2.addChild(scan.nextInt());
TreeNode node211 = node21.addChild(scan.nextInt());
int newK = scan.nextInt();
System.out.println(""+largerK(root, newK));
}

//Recursive implementation of largerK() method
   public static int largerK(TreeNode n, int k) {
       int v=0;
   if(n.data > k)
   v=1;
   for(TreeNode tn : n.getChildren())
   v += largerK(tn, k);
      return v;
   }

}

The sample output is given below: