What is the position of Q from the left end?

There are three persons sit between O and N. The person who sits two places away from N sits fourth to the right of M. M sits neither adjacent to O nor adjacent to S. The person who sits immediate left of the vacant seat sits two places away from O. Q does not sit adjacent to O. R sits two places away from Q. The number of persons who sits between N and R is one less than the number of persons who sits between S and Q. M does not sit at the end. Q does not sits right of N. T sits adjacent to N. This eliminates case 1a. The number of persons who sits between Q and P is same as the number of persons who sits between T and O. This eliminates case 1 and 1a. so final case-2 Case-2