Hello Sunil 

The gate score cutoff for 2018 is 16.6 and this is for SC/ST category for the computer science branch and also the gate qualifing mark will be released in March 16th 2019 so wait till that period sir because the competition is increasing year by year so we cannot tell accurate so please wait

I will provide link for more information

https://www.google.com/amp/s/engineering.careers360.com/articles/gate-cutoff/amp

Good luck