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Day 14 part 2

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Dece 2019-12-15 15:36:40 +01:00
parent eb858068dc
commit 2d9bba8a15
1 changed files with 15 additions and 28 deletions
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2019/day14.py
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@ -3,16 +3,6 @@ import math
import re import re
EX1 = [
"10 ORE => 10 A",
"1 ORE => 1 B",
"7 A, 1 B => 1 C",
"7 A, 1 C => 1 D",
"7 A, 1 D => 1 E",
"7 A, 1 E => 1 FUEL",
]
def main(): def main():
with open("day14.txt", "rt") as input_file: with open("day14.txt", "rt") as input_file:
lines = [line.rstrip() for line in input_file.readlines()] lines = [line.rstrip() for line in input_file.readlines()]
@ -28,7 +18,6 @@ def main():
# Part 1 # Part 1
ore_per_full = get_required_ore(reactions, 1) ore_per_full = get_required_ore(reactions, 1)
print("Required ore for 1 FUEL:", ore_per_full) print("Required ore for 1 FUEL:", ore_per_full)
return
# Part 2 # Part 2
# Input gives 397771 OPF. # Input gives 397771 OPF.
@ -38,28 +27,33 @@ def main():
# 10^12 / 82892753 / 13312 ~= 0.91 # 10^12 / 82892753 / 13312 ~= 0.91
# 10^12 / 5586022 / 180697 ~= 0.99 # 10^12 / 5586022 / 180697 ~= 0.99
# 10^12 / 460664 / 2210736 ~= 0.98 # 10^12 / 460664 / 2210736 ~= 0.98
# Let's say our reaction will have this value at about 0.985. # Let's say our reaction will have an efficiency of ~ 0.985.
# 10^12 / x / 397771 = 0.985 -> x = 2552294 # 10^12 / x / 397771 = 0.985 -> x = 2552294
# Now on to our search. # Now on to our search.
fuel_q = 2552294 fuel_q = 2552294
cursor = 10000 cursor = 2**16
last_result = 0 last_result = 0
min_target = 10**12 - ore_per_full min_target = 10**12 - ore_per_full
max_target = 10**12 max_target = 10**12
was_below = False was_below = False
was_above = False while True:
while last_result not in range(min_target, max_target):
last_result = get_required_ore(reactions, fuel_q) last_result = get_required_ore(reactions, fuel_q)
print("{} FUEL requires {} ORE.".format(fuel_q, last_result)) print(f"{fuel_q} FUEL requires {last_result} ORE.")
if cursor == 1:
break
if last_result < min_target: if last_result < min_target:
if was_above: if not was_below:
cursor /= 2 cursor //= 2
fuel += cursor fuel_q += cursor
was_below = True
elif last_result > max_target: elif last_result > max_target:
if was_below: if was_below:
cursor /= 2 cursor //= 2
fuel -= cursor fuel_q -= cursor
was_below = False
else:
break
def get_required_ore(reactions, quantity): def get_required_ore(reactions, quantity):
stored_map = collections.defaultdict(int) stored_map = collections.defaultdict(int)
@ -67,26 +61,19 @@ def get_required_ore(reactions, quantity):
ore_per_full = 0 ore_per_full = 0
while needs: while needs:
needed, needed_q = needs.pop(0) needed, needed_q = needs.pop(0)
print(f"Need {needed_q} {needed}.")
if needed == "ORE": if needed == "ORE":
print(f"- {needed_q} ORE required.")
ore_per_full += needed_q ore_per_full += needed_q
continue continue
react_mult, subcomps = reactions[needed] react_mult, subcomps = reactions[needed]
if stored_map[needed]: if stored_map[needed]:
print(f"- Already got {stored_map[needed]} in storage.")
needed_q -= stored_map[needed] needed_q -= stored_map[needed]
stored_map[needed] = 0 stored_map[needed] = 0
num_reacts = math.ceil(needed_q / react_mult) num_reacts = math.ceil(needed_q / react_mult)
print(f"- Requires {num_reacts} reaction(s) ({react_mult} {needed} per R)")
if num_reacts: if num_reacts:
new_needs = [(name_sc, num_sc * num_reacts) for num_sc, name_sc in subcomps] new_needs = [(name_sc, num_sc * num_reacts) for num_sc, name_sc in subcomps]
print(f"- New needs: {new_needs}")
needs += new_needs needs += new_needs
produced = react_mult * num_reacts produced = react_mult * num_reacts
print(f"- Produced {produced} {needed}.")
if produced - needed_q > 0: if produced - needed_q > 0:
print(f"- Stored {produced - needed_q} {needed} leftovers.")
stored_map[needed] += produced - needed_q stored_map[needed] += produced - needed_q
return ore_per_full return ore_per_full