Java Exercises: Check if two binary trees are identical or not

Java Basic: Exercise-182 with Solution

Write a Java program to check if two binary trees are identical or not. Assume that two binary trees have the same structure and every identical position has the same value.

Sample Solution:

Java Code:

import java.util.*;
public class Solution {  
   public static void main(String[] args) {
        TreeNode a = new TreeNode(1);
        a.left = new TreeNode(2);
        a.right = new TreeNode(3);
        a.left.left = new TreeNode(4);
		
		TreeNode b = new TreeNode(1);
        b.left = new TreeNode(2);
        b.right = new TreeNode(3);
        b.left.right = new TreeNode(4);
				
		TreeNode c = new TreeNode(1);
        c.left = new TreeNode(2);
        c.right = new TreeNode(3);
        c.left.right = new TreeNode(4);
		
        System.out.println("\nComparing TreeNode a and TreeNode b:");
        System.out.println(is_Identical_tree_node(a, b));
		System.out.println("\nComparing TreeNode b and TreeNode c:");
		System.out.println(is_Identical_tree_node(b, c));
    }

    public static boolean is_Identical_tree_node(TreeNode a, TreeNode b) {
        // Write your code here
        if (a == null && b == null) return true;
        if (a == null || b == null) {
            return false;
        }
        if (a.val != b.val) return false;
        return is_Identical_tree_node(a.left, b.left) &&
                is_Identical_tree_node(a.right, b.right);
    }
}
class TreeNode {
    public int val;
    public TreeNode left, right;
    public TreeNode(int val) {
        this.val = val;
        this.left = this.right = null;
    }
}

Sample Output:

Comparing TreeNode a and TreeNode b:
false

Comparing TreeNode b and TreeNode c:
true

Flowchart:

Java Code Editor:

Company:  Bloomberg

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