Dickensian Dictionary

You are stuck in your job at the Boring Accountancy Platform Company; the entire day you have to code all kinds of programs that you do not care about. This involves a lot of tedious typing, which you do not want to do. To pass the time, you decide to interact with the words you type more playfully. In particular, you really enjoy it when you type a word with your left and right hand alternating. You dub these words Dickensian.

Your mind is quickly overwhelmed with Dickensian words, and even at home they still dictate your thoughts. You want to gather as many Dickensian words as possible and start coding. Given a word, you will need to decide if it is Dickensian or not.

The letters you can type with your left hand are "qwertasdfgzxcvb", and the letters you can type with your right hand are "yuiophjklnm".

The input consists of:

• One line containing a string of length at least $2$ and at most $20$, consisting of lowercase characters a-z.

Output "yes" if the input string is Dickensian, and "no" otherwise.