2020 day1/python: modify for part2

This commit is contained in:
Xiretza 2020-12-01 16:50:45 +01:00
parent e78a627f19
commit 486b5e779c

View file

@ -1,15 +1,22 @@
#!/usr/bin/env python
import itertools
import sys
from typing import Iterable
def find2020(nums: Iterable[int]) -> int:
candidates = set()
def product(nums: Iterable[int]) -> int:
"""
Returns the product of all elements in 'nums'
"""
x = 1
for num in nums:
opposite = 2020-num
if num in candidates:
return num * opposite
candidates.add(opposite)
x *= num
return x
def find_summing(arity: int, nums: Iterable[int]) -> int:
return product(next(filter(lambda xs: sum(xs) == 2020, itertools.permutations(nums, r=arity))))
if __name__ == '__main__':
with open(sys.argv[1], 'r') as f:
print(find2020(int(n) for n in f.readlines()))
nums = [int(n) for n in f.readlines()]
print(find_summing(2, nums))
print(find_summing(3, nums))