Directions : Question is based on the following information:
I. Six flats on a floor in two rows facing North and South are allotted to P, Q, R, S, T and U.
II. Q gets a North facing flat and is not next to S.
III. S and U get diagonally opposite flats.
IV. R next to U, gets a south facing flat and T gets North facing flat.
Whose flat is between Q and S?