Root Equals Sum of Children Solution in Java

Problem Description

Welcome to the whimsical world of binary trees, where every node has a value, and the root node is supposed to be the wise elder that knows the sum of its children! The problem at hand is as simple as pie (or should I say, as simple as a tree?). You are given a binary tree, and your task is to check if the value of the root node is equal to the sum of the values of its left and right children.

Imagine a family dinner where the parents (the root) are supposed to know how much their kids (the left and right children) ate. If the parents don’t know, well, let’s just say they might need to reconsider their parenting skills!

Code Solution



class Solution {

  public boolean checkTree(TreeNode root) {

    return root.val == root.left.val + root.right.val;

  }

}

Approach

The approach here is straightforward: we simply compare the value of the root node with the sum of its left and right children. If they match, we return true; otherwise, we return false. It’s like checking if your bank account balance matches your spending—if it doesn’t, you might want to check your receipts!

Time and Space Complexity

Time Complexity: O(1) – We are only performing a constant number of operations regardless of the size of the tree.

Space Complexity: O(1) – We are using a constant amount of space.

Real-World Example

Think of a family where the parents are trying to keep track of their kids’ allowances. If the kids claim they spent all their allowance on candy, the parents will check if the total amount they gave matches the sum of what the kids say they spent. If it doesn’t add up, someone is definitely hiding some candy!