LeetCode 112. Path Sum Add to List

Given a binary tree and a sum, determine if the tree has a root-to-leaf path such that adding up all the values along the path equals the given sum. For example:
Given the below binary tree and sum = 22,

              5             / \            4   8           /   / \          11  13  4         /  \      \        7    2      1

return true, as there exist a root-to-leaf path 5->4->11->2 which sum is 22.

/** * Definition for a binary tree node. * public class TreeNode { *     int val; *     TreeNode left; *     TreeNode right; *     TreeNode(int x) { val = x; } * } */public class Solution {    public boolean hasPathSum(TreeNode root, int sum) {        boolean left=false,right=false;        if(root == null){            return false;        }else if(root.left==null && root.right==null){            if(root.val==sum ){                return true;            }else{                return false;            }        }else {            sum = sum -root.val;            left = hasPathSum(root.left,sum);            right = hasPathSum(root.right,sum);                  return left || right;        }    }}