Maximum Level Sum in a Binary Tree

Java Implementation of finding the maximum level sum in a binary tree iteratively.

import java.util.LinkedList;
import java.util.Queue;

class Solution
{
    static class TreeNode{
        int data;
        TreeNode left,right;
        TreeNode(int data)
        {
            this.data=data;
        }
    }
    static int maxLevelSum(TreeNode root)
    {
        int max=Integer.MIN_VALUE;
        Queue<TreeNode> queue=new LinkedList<>();
        queue.add(root);
        while(!queue.isEmpty())
        {
            int s=queue.size();
            int levelsum=0;
            for(int i=0;i<s;i++)
            {
                
                TreeNode temp=queue.poll();
                if(temp.left!=null)
                queue.add(temp.left);
                if(temp.right!=null)
                queue.add(temp.right);
                
                levelsum=levelsum+temp.data;
            }
            if(levelsum>max)
                max=levelsum;
        }
        return max;
    }
     public static void main(String[] args)
    {
        TreeNode root=new TreeNode(1);
        root.left=new TreeNode(2);
        root.right=new TreeNode(3);
        root.left.left=new TreeNode(4);
        root.left.right=new TreeNode(7);
        
        int max=maxLevelSum(root);
        System.out.println(max);
        
         
    }
    }

Output: 11

Time Complexity- O(n)

Space Complexity- O(n)

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