equal-tree-partition

gistfile1.txt

/**
 * Definition for a binary tree node.
 * public class TreeNode {
 *     int val;
 *     TreeNode left;
 *     TreeNode right;
 *     TreeNode(int x) { val = x; }
 * }
 */
class Solution {
    public boolean checkEqualTree(TreeNode root) {
        return checkValid(getSum(root), root, root);
    }
    public int getSum(TreeNode node) {
        if(node == null)
            return 0;
        int sum = node.val + getSum(node.left) + getSum(node.right);
        return sum;        
    }
    public boolean checkValid(int sum, TreeNode root, TreeNode curr) {
        if(curr == null)
            return false;
        return checkValid(sum, root, curr.left) || checkValid(sum, root, curr.right) || (root != curr && sum == 2*getSum(curr));
    }
}