Since you've indicated you're using release R2012a, the string data type introduced in release R2016b isn't an option for you. [If upgrading is an option, I would recommend doing so as that would let you use string.]
So you're going to need to make either a char array or a cell array containing char vectors. Search your locally installed documentation for the three word phrase "Creating Character Arrays" and read the first two hits for information on how to use each of these two techniques.
