Day 20 - Advent of Code 2015

""" day_20_01.py """

# usage: python3 day_20_01.py < input

import math


def sum_factors(dividend):
    """ sum factors of dividend """
    factors = set()
    limit = int(math.sqrt(dividend))
    for i in range(1, limit + 1):
        quotient, remainder = divmod(dividend, i)
        if remainder == 0:
            factors.add(i)
            factors.add(quotient)
    return sum(factors)


presents = int(input())

house = 1
while sum_factors(house) * 10 < presents:
    house += 1
print(house)

""" day_20_02.py """

# usage: python3 day_20_02.py < input

import math


def sum_limited_factors(dividend):
    """ sum limited factors of dividend """
    factors = set()
    limit = int(math.sqrt(dividend))
    for i in range(1, limit + 1):
        quotient, remainder = divmod(dividend, i)
        if remainder == 0:
            if quotient <= 50:
                factors.add(i)
            if i <= 50:
                factors.add(quotient)
    return sum(factors)


presents = int(input())

house = 1
while sum_limited_factors(house) * 11 < presents:
    house += 1
print(house)