@@ -0,0 +1,356 @@
+%0D%0Apublic class _331VerifyPreorderSerializationOfABinaryTree %7B%0D%0A    public boolean isValidSerialization(String preorder) %7B%0D%0A        String%5B%5D s = preorder.split(%22,%22);%0D%0A        int nulls = 1;%0D%0A        for (String str : s) %7B%0D%0A        %09if (--nulls %3C 0) return false;%0D%0A        %09if (!str.equals(%22#%22)) nulls += 2;%0D%0A        %7D%0D%0A        return nulls == 0;%0D%0A    %7D%0D%0A%7D%0D%0A

Add 331 solution