I haven't studied your code but mine stumbled over this input line at one point:
eightjzqzhrllg1oneightfck
Simpler test:
12 oneight
Should yield 18 for part 2.
I haven't studied your code but mine stumbled over this input line at one point:
eightjzqzhrllg1oneightfck
Simpler test:
12 oneight
Should yield 18 for part 2.
Thank you for the test case! I went out for dinner but I'll work on this tomorrow. I strongly suspect this is the exact issue but I'm going to have to rework some things so I want to tackle it with a fresh mind.
Thanks for this. Solved my problem.
I think it's related to the replacement of words with digits. There are some overlapping words, for example in "eightwothree" the "t" is used for both "eighT" and "Two". In this case the order of replacement differs your result. It either becomes "8wo3" or "eigh23".
I think you may be right but the problem is at the end of the string. I'll add some test cases and rewrite the code. I think I'll have to ditch the regex replacements and scan through instead so I don't clobber the string in the wrong place.
Do share if you find the input that was causing trouble, I'm tripping on some miniscule error as well and i have no idea what could it be
I just added this to my test case and when it passed the solution also passed:
assert part2("12oneightfve") === 18
I arrived at the following solution for Day #1:
defmodule AdventOfCode.Day01 do
def part1(args) do
number_regex = ~r/([0-9])/
args
|> String.split(~r/\n/, trim: true)
|> Enum.map(&first_and_last_number(&1, number_regex))
|> Enum.map(&number_list_to_integer/1)
|> Enum.sum()
end
def part2(args) do
number_regex = ~r/(?=(one|two|three|four|five|six|seven|eight|nine|[0-9]))/
args
|> String.split(~r/\n/, trim: true)
|> Enum.map(&first_and_last_number(&1, number_regex))
|> Enum.map(fn number -> Enum.map(number, &replace_word_with_number/1) end)
|> Enum.map(&number_list_to_integer/1)
|> Enum.sum()
end
defp first_and_last_number(string, regex) do
matches = Regex.scan(regex, string)
[_, first] = List.first(matches)
[_, last] = List.last(matches)
[first, last]
end
defp number_list_to_integer(list) do
list
|> List.to_string()
|> String.to_integer()
end
defp replace_word_with_number(string) do
numbers = ["one", "two", "three", "four", "five", "six", "seven", "eight", "nine"]
String.replace(string, numbers, fn x ->
(Enum.find_index(numbers, &(&1 == x)) + 1)
|> Integer.to_string()
end)
end
end
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Advent of Code is an annual Advent calendar of small programming puzzles for a variety of skill sets and skill levels that can be solved in any programming language you like.
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console.log('Hello World')