Need a laptop but I don't know which one will suit me?

I am studying computer science and it's my second semester and I am the only one who think laptops aren't so useful because I do my all works on my desktop and I am the only one in my class still don't have laptop.

So, I decided to buy one or I wait?
Well I am still using visual studio (c++) and in my second year we will use c# and java and my third year I will take (AI, graphics, data structure, etc)

what kind of laptops will suit me and I want it too suit me till my third year at least?

well, macbook pro 13' retina display will be out as I can't offered it right now.

I was think xps 14z or 15z?
and xps or inspiron?

feel free to recommend me any kind of laptops.

Thanks in advance.