Deal vector to function inputs

Hello,

My problem is as follows:

1. I create a function using syms as follows:

   syms x y
   f = @(x,y) x+y;

2. Now I assign a vector or a cell array and I want something as follows:

 A = {1,2};
y(deal(A{:}) = 3

I basically looking for a way to make this work for any number of variables. Thank you

UPDATE: never mind I have found it: http://stackoverflow.com/questions/4755324/in-matlab-for-a-multiple-input-function-how-to-use-a-single-input-as-multiple