Find maximum/ largest element in a binary tree ( java/ BFS / example)

Given a binary tree, find out the maximum or largest element using non recursive algorithm.
Traverse the binary tree using depth first search (DFS) or level order traversal.

Maximum element binary tree — Fig 1: Max element in binary tree

Example: Maximum element in a binary tree using java

Create max variable to denote largest element in a binary tree.
Visit the Level 0 and maximum value will be set to 50[Refer Fig 1]
Go to Level 1 & visit all nodes
- Visit Node 25, which is less than current max value 50
  - max value will not be updated
- Visit Next node 30, which is less the current max 50
  - max value will not be updated
Go to Level 2 & visit all nodes
- Node D, Node E & Node F are less than current max value.
  - max value will not be updated
- When we visited Node G.
  - max value is greater than current max, so max will be updated to 60.
Maximum or largest element in a binary tree is 60.
Visited all nodes [Refer Fig 2]

largest element level binary tree — Fig 2: Max element at each level

Time complexity of algorithm is O(n).

Program: Maximum or largest element – binary tree

1.) MaxElement Class:

MaxElement class is responsible for finding the maximum or largest element in a binary tree.
Traverse the binary tree using level order traversal or breadth first search (non recursive) algorithm.

package org.learn.Question;
 
import java.util.LinkedList;
import java.util.Queue;
 
public class MaxElement {
    public static int maxElement(Node root) {
        if (root == null) {
            System.out.println("Tree is empty");
            return Integer.MIN_VALUE;
        }
        int max = root.data;
        Queue<Node> queue = new LinkedList<Node>();
        queue.offer(root);
 
        while (!queue.isEmpty()) {
            Node node = queue.poll();
            if(max < node.data) {
                max = node.data;
            }
            if (node.left != null) {
                queue.offer(node.left);
            }
            if (node.right != null) {
                queue.offer(node.right);
            }
        }
        System.out.println("Max Element in Binary Tree is : " + max);
        return max;
    }
}

2.) Node Class:

Node class is representing the node(s) of a binary tree.

package org.learn.Question;
 
public class Node {
    public int data;
    public Node left;
    public Node right;
 
    public Node(int num) {
        this.data = num;
        this.left = null;
        this.right = null;
    }
 
    public Node() {
        this.left = null;
        this.right = null;
    }
     
    public static Node createNode(int number) {
        return new Node(number);
    }
}

3.) App Class:

We are creating a binary tree in main method.
We are calling method of maxElement class to find maximum element in a binary tree

package org.learn.Client;
 
import org.learn.Question.MaxElement;
import org.learn.Question.Node;
 
public class App {
    public static void main(String[] args) {
        // root level 0
        Node A = Node.createNode(50);
        // Level 1
        Node B = Node.createNode(25);
        Node C = Node.createNode(30);
        // Level 2
        Node D = Node.createNode(40);
        Node E = Node.createNode(10);
        Node F = Node.createNode(30);
        Node G = Node.createNode(60);
         
        // connect Level 0 and 1
        A.left = B;
        A.right = C;
        // connect level 1 and level 2
        B.left = D;
        B.right = E;
        C.left = F;
        C.right = G;
        // connect level 2 and level 3
        MaxElement.maxElement(A);
    }
}

Output : maximum or largest element in binary tree (Java/BFS)

Max Element in Binary Tree is : 60

Example: Maximum element in a binary tree using java

Program: Maximum or largest element – binary tree

1.) MaxElement Class:

2.) Node Class:

3.) App Class:

Output : maximum or largest element in binary tree (Java/BFS)

You may also like: