Hey!

First of all congratulations on your rank. And now to answer your question it's hard to be precise about the cutoff but you can have an expected cutoff by referring to previous year cutoff. You can check the previous years cutoff using the provided link https://engineering.careers360.com/articles/comedk-uget-cutoff

Although, if you are looking to get an admission in the top 15 colleges in cs branch chances are very slim for that. If you are fixated on one of the top 15 colleges you might want to consider other branches. Hope this was helpful. All the best.