def defensible(pw: planet_wars.PlanetWars, planet: planet_wars.Planet):
quickest_planet = min(pw.my_planets(),
key=lambda p: turn_to_take(pw, p, planet))
quickest_turns = turn_to_take(pw, quickest_planet, planet)
for t in range(quickest_turns + 1,
furthest_meaningful_planet(pw, planet, 2) + 2):
my_maximum_ships = max(
0,
sum(planet.my_maximum_ships[:t - 1]) - planet.num_ships() +
planet.growth_rate() * (t - quickest_turns))
enemy_maximum_ships = sum(planet.enemy_maximum_ships[:t])
if my_maximum_ships < enemy_maximum_ships:
return False
return True
def turn_to_take(pw: planet_wars.PlanetWars, my_planet: planet_wars.Planet,
neutral_planet: planet_wars.Planet):
"""
Finds the minimum turns to take `neutral_planet` with `my_planet`.
:param pw: `PlanetWars` object
:param my_planet: `Planet` object
:param neutral_planet: `Planet` object
:return: `int` turns to take the planet
"""
distance = pw.distance(my_planet.planet_id(), neutral_planet.planet_id())
if my_planet.num_ships() > neutral_planet.num_ships():
return distance
else:
lacking_ships = neutral_planet.num_ships() - my_planet.num_ships() + 1
for t in range(pw.map_size):
lacking_ships -= my_planet.my_arriving_ships[
t] + my_planet.growth_rate()
if lacking_ships <= 0:
break
else:
return 999999
return distance + t
