[LeetCode]129 Sum Root to Leaf Numbers

/**
* Definition for binary tree
* public class TreeNode {
*     int val;
*     TreeNode left;
*     TreeNode right;
*     TreeNode(int x) { val = x; }
* }
*/
public class Solution {
public int sumNumbers(TreeNode root) {

if (root == null)
return 0;

Result result = new Result();
visit(root, 0, result);
return result.value;
}

private void visit(TreeNode node, int value, Result result)
{
int newvalue = value * 10 + node.val;
if (node.left == null && node.right == null)
{
result.value +=  newvalue;
return;
}

if (node.left != null)
visit(node.left, newvalue, result);

if (node.right != null)
visit(node.right, newvalue, result);
}

static class Result
{
int value;
}
}