NYU/Columbia Summer programs?

<p>I'm currently a junior in HS, and I want to go to NYU/Columbia/Stony Brook. I want to major in computer science, so I'm thinking about attending NYU's or Columbia's summer program come the summer of junior year. I was just wondering what I need to get into these programs and what the time/travel commitment would be (I live in Putnam County, NYS). In addition, can anyone maybe tell me what it's like to be in these programs?</p>