Day 4 part 1

This commit is contained in:
Daniel Flanagan 2023-12-09 10:52:38 -06:00
parent 907385eb70
commit 02e78aea8f
Signed by: lytedev
GPG key ID: 5B2020A0F9921EF4

83
2023/rust/src/day4.rs Normal file
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mod prelude;
extern crate nom;
use nom::{
branch::alt,
bytes::complete::{tag, take_while},
character::complete::space1,
combinator::{map_res, value},
multi::separated_list0,
sequence::tuple,
IResult,
};
use std::{collections::HashSet, iter::FromIterator};
use crate::prelude::*;
fn main() {
Day4::show(day_input(4), day_input(4))
}
#[derive(Debug)]
struct Card {
id: usize,
winning: HashSet<usize>,
has: Vec<usize>,
}
impl Card {
fn points(&self) -> usize {
let num_winning = self.has.iter().filter(|n| self.winning.contains(n)).count() as u32;
println!("{self:?} num_winning -> {num_winning}");
if num_winning >= 1 {
2_u64.pow(num_winning - 1) as usize
} else {
0
}
}
}
// parser
fn int(input: &str) -> IResult<&str, usize> {
map_res(take_while(char::is_numeric), str::parse)(input)
}
fn card(input: &str) -> IResult<&str, Card> {
let (input, id) = int(tuple((tag("Card"), space1))(input)?.0)?;
let (input, winning_list) = separated_list0(space1, int)(tuple((tag(":"), space1))(input)?.0)?;
let (input, has) = separated_list0(space1, int)(tuple((space1, tag("|"), space1))(input)?.0)?;
let winning = HashSet::from_iter(winning_list);
Ok((input, Card { id, winning, has }))
}
struct Day4 {}
impl Day4 {}
impl AoCSolution for Day4 {
type Input = String;
type Solution = usize;
fn part1(input: Self::Input) -> Self::Solution {
input.lines().map(|s| card(s).unwrap().1.points()).sum()
}
fn part2(input: Self::Input) -> Self::Solution {
0
}
}
#[cfg(test)]
mod tests {
use super::*;
#[test]
fn test() {
let input = r#"Card 1: 41 48 83 86 17 | 83 86 6 31 17 9 48 53
Card 2: 13 32 20 16 61 | 61 30 68 82 17 32 24 19
Card 3: 1 21 53 59 44 | 69 82 63 72 16 21 14 1
Card 4: 41 92 73 84 69 | 59 84 76 51 58 5 54 83
Card 5: 87 83 26 28 32 | 88 30 70 12 93 22 82 36
Card 6: 31 18 13 56 72 | 74 77 10 23 35 67 36 11"#;
println!("input:\n{input}");
assert_eq!(Day4::part1(input.into()), 13);
assert_eq!(Day4::part2(input.into()), 0);
}
}