mas = 1
edad = 18
prot = 0
est = 0
col = 1
if mas == 1:
    if edad >= 18:
        if prot == 0:
            if est == 0:
                if col == 1:
                    print "Prestar servicio"
                else:
                    print "no presta servicio"
            else:
                print "no presta servicio"
        else:
            print "no presta servicio"
    else:
        print "no presta servicio"
else:
    print "no presta servicio"