AoC 2020: day1, refactoring for O(n), O(n^2)

Signed-off-by: Ettore Dreucci <ettore.dreucci@gmail.com>
This commit is contained in:
2020-12-06 16:40:17 +01:00
parent cc5e210930
commit 42cf587323

View File

@@ -3,39 +3,40 @@
import pathlib import pathlib
import time import time
def read_input(input_path: str) -> list: def read_input(input_path: str) -> tuple:
"""take input file path and return appropriate data structure""" """take input file path and return appropriate data structure"""
with open(input_path, 'r') as input_file: with open(input_path, 'r') as input_file:
entries = list() entries = list()
is_present = [False]*2020
for entry in input_file.readlines(): for entry in input_file.readlines():
entries.append(int(entry)) entries.append(int(entry))
return entries is_present[int(entry)-1] = True
return (entries, is_present)
def part1(entries: list) -> int: def part1(entries: list, is_present: list) -> int:
"""part1 solver take a list of int and return an int""" """part1 solver take a list of int and a list of bool and return an int"""
for x in entries: for x in entries:
complement = 2020 - x complement = 2020 - x
if complement in entries: if complement > 0 and is_present[complement-1]:
return x * complement return x * complement
return None return None
def part2(entries: list) -> int: def part2(entries: list, is_present: list) -> int:
"""part2 solver take a list of int and return an int""" """part2 solver take a list of int and a list of bool and return an int"""
for x, i in enumerate(entries): for x, i in enumerate(entries):
for y in entries[i:]: for y in entries[i:]:
complement = 2020 - x - y complement = 2020 - x - y
if complement in entries: if complement > 0 and is_present[complement-1]:
return x * y * complement return x * y * complement
return None return None
def main(): def main():
"""main function""" """main function"""
input_path = str(pathlib.Path.cwd()) + "/inputs/" + str(pathlib.Path(__file__).stem) input_path = str(pathlib.Path(__file__).resolve().parent.parent) + "/inputs/" + str(pathlib.Path(__file__).stem)
entries = read_input(input_path) entries, is_present = read_input(input_path)
start_time = time.time() start_time = time.time()
print("Part 1: %d" % part1(entries)) print("Part 1: %d" % part1(entries, is_present))
print("Part 2: %d" % part2(entries)) print("Part 2: %d" % part2(entries, is_present))
end_time = time.time() end_time = time.time()
print("Execution time: %f" % (end_time-start_time)) print("Execution time: %f" % (end_time-start_time))