I read a book long back and I have searched for years but I am not able to find the book again or any reference to it.
So this book is about a scientist (a math genius) who is working on a top secret super computer. Since he is doing that, of course there are enemies who want to kill him. Two people (I think, a boy and a girl) come there. The scientist has a daughter who is a special kid and for the same, the scientist takes care of her all by himself. The scientist dies and the boy and the girl take charge of finding the culprit.
They find that there is a hidden room in the house... the little girl is a math genius and a prodigy by all means. She too calculates the volume of her home and all rooms and finds the exact location of the room.
In the end it is discovered that the little girl was the super computer that the scientist was working on.
Edited details : Its in English. Its a proper novel and not a short story.