It's definitly possible, especially with the lucky egg given by Happiney, the method would be first involve only studying your electives until they reach 20-30 (this limits who you hangout with), than you either win or lose every battle I recommend loss since you gain more exp that way, when you train at the fields keep using a mon until they faint leaving the last mon on low hp, leave and you'll get the bonus exp, once Silver's gang and the alleyway are available stop going to the fields and repeat at the city using every chance to fight Silver's gang, afterwards get Happiney so you recieve the lucky egg, now add it to the trianing strategy by giving it to a mon and once they faint give it to the next mon...etc, once you reach the Seaport repeat and you'll pretty much at the max cap. You also get free exp by simply going to a battle team meeting, and this gives a lot of free exp without even trying.