Got groped at in train right now

Was in a crowded train right now at 1.35 pm (Sudden crowd at Dadar) .The man opposite me put his hand over my pants . I felt it would be accidental considering the crowd .Told him I would throw his ass of the train and he insticintevly got scared and deboarded the train . I was in shock . I couldnt react afterwards . I am still in shock . I am a guy btw \ Edit : I feel weird . Disgusted . There is some weird sensation of disgust at my own body . I have this urge to pee but that outward sensation just makes me more disgusted about my own body . \ Edit : Thank you all for your kind words ! I am sorry I couldn't respond sooner . Also just to let everyone know , its very difficult to react or slap or shout .Not because I am weak or scared or anything. Its almost shocking .I have been in Mumbai forever .I have travelled trains for more than a decade so such an experience was shocking .Its not easy to react . Simply because you dont know what to register . Add to that the crowd , and him just running away . But again thank you all !