What is a dctp and did in my internal storage? It has no file extension

[AC Question]

My phone is a Xiaomi Redmi Note 3

 

[Rishu_019]

So, I have 3 Mi note 4s and each one of them contains dctp and did in their internal storage.... And it should be deleted as it is making my phone slower and sometimes automatic phone turns off.... But, I don't know, if they r any kind of viruses or what???