Lets say I've got 4 weedles, 1 kakuna and 50 weedle candies. A weedle needs 12 candies to evolve, and a kakuna needs 50. Would I get more XP if I evolve the 4 weedles or the 1 kakuna? And whichever gives the greater XP, would the same principle apply to evolving other Pokémon?