@@ -14,24 +14,23 @@
 * }
 */
 class Solution {
-public int averageOfSubtree(TreeNode root) {
-int[] result = {0};
-helper(root, result);
-return result[0];
-}
-
-private int[] helper(TreeNode root, int[] result) {
-if (root == null) {
-return new int[]{0, 0};
+public int averageOfSubtree(TreeNode root) {
+int[] result = {0};
+recurse(root, result);
+return result[0];
 }
-int[] left = helper(root.left, result);
-int[] right = helper(root.right, result);
-int sum = left[0] + right[0] + root.val;
-int numOfNodes = left[1] + right[1] + 1;
-int average = sum / numOfNodes;
-if (root.val == average) {
-result[0]++;
+
+private int[] recurse(TreeNode root, int[] result) {
+if (root == null) {
+return new int[]{0, 0};
+}
+int[] left = recurse(root.left, result);
+int[] right = recurse(root.right, result);
+int sum = left[0] + right[0] + root.val;
+int count = left[1] + right[1] + 1;
+if (count != 0 && sum / count == root.val) {
+result[0]++;
+}
+return new int[]{sum, count};
 }
-return new int[]{sum, numOfNodes};
-}
 }