Among six persons, P, Q, R, S, T and U, each one has a different weight. The weight of Q is more than only two other persons. The weight of P is more than U's weight. The weight of S is more than Q's weight. The weight of R is less than the weight of T. The weight of Q is more than the weight of T. U has the second highest weight among all the six persons. Who has the third highest weight among all six persons?