A string $T$ is called a 1122 string if and only if it satisfies all of the following three conditions:

• $\lvert T \rvert$ is even. Here, $\lvert T \rvert$ denotes the length of $T$.
• For each integer $i$ satisfying $1\leq i\leq \frac{|T|}{2}$, the $(2i-1)$-th and $2i$-th characters of $T$ are equal.
• Each character appears in $T$ exactly zero or two times. That is, every character contained in $T$ appears exactly twice in $T$.

Given a string $S$ consisting of lowercase English letters, print Yes if $S$ is a 1122 string, and No otherwise.

The input is given from Standard Input in the following format:

$S$

If $S$ is a 1122 string, print Yes; otherwise, print No.

• $S$ is a string of length between $1$ and $100$, inclusive, consisting of lowercase English letters.

$S=$aabbcc satisfies all the conditions for a 1122 string, so print Yes.

$S=$aab has an odd length and does not satisfy the first condition, so print No.

$S=$zzzzzz contains six zs and does not satisfy the third condition, so print No.