hi aspirant ,

CS is not a subject in IES exam . only electrical , mechanical , civil , electronics & telecommunication engineering students can give IES exam. If you want to give IES exam try out with electronics and telecommunication branch , but in this you have to study all 4 years syllabus of this branch . for more information you can check out this link - https://engineering.careers360.com/articles/cracking-ies-stable-career-assured-growth-trajectory