23.
Each of P, Q, R, S, T, U and V has an exam on a different day of a week starting from Monday and ending on Sunday of the same week. V has an exam on Thursday. Exactly 4 people have their exams between U and Q, neither of whom has an exam on Sunday. T has an exam immediately before S. R does not have an exam on Friday. U does not have an exam after S. How many people have exams after Q?