Find A Solution That 'Set'isfy The Problem...

$P$ is a set containing $6$ elements. A subset $A$ of $P$ is chosen and the set $P$ is reconstructed by replacing the elements of $A$ . Now a subset $B$ of $P$ is chosen again.

If the number of ways of choosing $A$ and $B$ such that $B$ contains just $1$ element more than $A$ is $x$

And

The number of ways of choosing $A$ and $B$ such that $B$ is a subset of $A$ is $y$ .

Find $y - x$