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advent-of-code/2020/days/01/day1.py

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1.4 KiB
Python
Executable file

#! /usr/bin/env python3
import pathlib
import sys
def parse(puzzle_input):
"""Parse input"""
return [int(string) for string in puzzle_input.splitlines()]
def part1(data: list[int]):
"""Solve part 1"""
data.sort()
while True:
if len(data) < 2:
raise ValueError("no match found")
s = data[0] + data[-1]
if s > 2020:
data.pop(-1)
elif s < 2020:
data.pop(0)
else:
return data[0] * data[-1]
def part2(data):
"""Solve part 2"""
data.sort()
while True:
if len(data) < 3:
raise ValueError("no match found")
if data[0] + data[1] + data[-1] > 2020:
data.pop(-1)
elif data[0] + data[-1] + data[-2] < 2020:
data.pop(0)
elif data[0] + data[1] + data[-1] == 2020:
return data[0] * data[1] * data[-1]
else:
return data[0] * data[-1] * data[-2]
def solve(puzzle_input):
"""Solve the puzzle for the given input"""
data = parse(puzzle_input)
solution1 = part1(data.copy())
solution2 = part2(data.copy())
return solution1, solution2
if __name__ == "__main__":
for path in sys.argv[1:]:
print(f"{path}:")
puzzle_input = pathlib.Path(path).read_text().strip()
solutions = solve(puzzle_input)
print("\n".join(str(solution) for solution in solutions))