AdventOfCode/2015/day20.py

16 lines
507 B
Python

import numpy as np
max_it = 813960 # Somewhat cheaty - this value was obtained from an earlier factor-based brute force. Just use an arbitrarily large number if it fails.
input = 33100000
houses = np.ones([max_it], dtype=np.int64)
pres10 = input//10
for i in range(2, max_it):
houses[i::i] += i
print(np.argmax(houses > pres10)) # Part 1
houses_2 = np.ones([max_it], dtype=np.int64)
pres11 = input//11
for i in range(2, max_it):
houses_2[i:i*51:i] += i
print(np.argmax(houses_2 > pres11)) # Part 2