Fastest way to compare two arrays

I have two arrays

The objects are server,sharename,path   

I created two variables one for each system,  The shares are 15K plus.

So, I was trying to find the differences and then spit the differences from one site and if there are differences, then just add action..

Is this the best way to do this.

diff $nj $pa -property sharename 

But then I only want to take action on the differences in PA

so I was thinking to pipe that to 

% {

add-sharecmdlet 

}

Is that even possible?