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advent_of_code/2023/day_5/part 2 solution.py
T
2023-12-05 08:09:00 +00:00

72 lines
3.1 KiB
Python

with open(r'advent_of_code\2023\day_5\input.txt', 'r') as file:
input = file.readlines()
with open(r'advent_of_code\2023\day_5\test_input.txt', 'r') as file:
test_input = file.readlines()
#input = test_input
# print(input)
# find the seed numbers
seed_numbers = input[0].split(':')[1].strip().split(' ')
#print(seed_numbers)
#first we need to split the seed map into lists of 2 numbers
seed_map = []
for i in range(0, len(seed_numbers), 2):
seed_map.append(seed_numbers[i:i+2])
#print(seed_map)
# find the instructions
line_seed_to_soil_map = input.index('seed-to-soil map:\n')
line_soil_to_fertilizer_map = input.index('soil-to-fertilizer map:\n')
line_fertilizer_to_water_map = input.index('fertilizer-to-water map:\n')
line_water_to_light_map = input.index('water-to-light map:\n')
line_light_to_temperature_map = input.index('light-to-temperature map:\n')
line_temperature_to_humidity_map = input.index('temperature-to-humidity map:\n')
line_humidity_to_location_map = input.index('humidity-to-location map:\n')
# get the instructions for each map
seed_to_soil_map_instructions = input[line_seed_to_soil_map+1:line_soil_to_fertilizer_map]
soil_to_fertilizer_map_instructions = input[line_soil_to_fertilizer_map+1:line_fertilizer_to_water_map]
fertilizer_to_water_map_instructions = input[line_fertilizer_to_water_map+1:line_water_to_light_map]
water_to_light_map_instructions = input[line_water_to_light_map+1:line_light_to_temperature_map]
light_to_temperature_map_instructions = input[line_light_to_temperature_map+1:line_temperature_to_humidity_map]
temperature_to_humidity_map_instructions = input[line_temperature_to_humidity_map+1:line_humidity_to_location_map]
humidity_to_location_map_instructions = input[line_humidity_to_location_map+1:]
def map_value(value, instructions):
for instruction in instructions:
instruction = instruction.strip() # remove newline character
if instruction: # check if instruction is not empty
destination_start, source_start, length = map(int, instruction.split())
if source_start <= value < source_start + length:
return destination_start + (value - source_start)
return value # if value is not in any range, it maps to itself
# Initialize the smallest location to a large number
smallest_location = float('inf')
for seed in seed_map:
start = int(seed[0])
count = int(seed[1])
for seed_number in range(start, start + count):
soil = map_value(seed_number, seed_to_soil_map_instructions)
fertilizer = map_value(soil, soil_to_fertilizer_map_instructions)
water = map_value(fertilizer, fertilizer_to_water_map_instructions)
light = map_value(water, water_to_light_map_instructions)
temperature = map_value(light, light_to_temperature_map_instructions)
humidity = map_value(temperature, temperature_to_humidity_map_instructions)
location = map_value(humidity, humidity_to_location_map_instructions)
# Update smallest_location if a smaller location is found
if location < smallest_location:
smallest_location = location
# Print the smallest location
print(smallest_location)