def before_2(x): return P(P(P(P(P(x)))))
def after(x): return P(15) + Q(x)
def before_1(x): return P(P(x))
def after(x): return P(x)
def before_2(x): return P(P(P(P(P(x)))))
def after(x): return P(15) + Q(x)
def before_1(x): return P(P(x))
def after(x): return P(x)