129. Sum Root to Leaf Numbers (java)

Author: bluesword12350

solution/0129.Sum Root to Leaf Numbers/Solution.java

@@ -0,0 +1,11 @@
+class Solution {
+    public int sumNumbers(TreeNode root) {
+        return sumNumbers(root,0);
+    }
+    private int sumNumbers(TreeNode root, int sum) {
+        if (root==null) return 0;
+        sum = sum *10 + root.val;
+        if (root.left==null && root.right==null) return sum;
+        return sumNumbers(root.left,sum)+sumNumbers(root.right,sum);
+    }
+}