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#![allow(dead_code)]
#![allow(unused_variables)]
use advent_of_code::prelude::*;
fn from_snafu(line: String) -> i64 {
let mut total = 0;
for c in line.chars() {
let digit = match c {
'2' => 2,
'1' => 1,
'0' => 0,
'-' => -1,
'=' => -2,
_ => panic!("unknown char {}", c),
};
total *= 5;
total += digit;
}
total
}
fn to_snafu(mut n: i64) -> String {
let mut s = String::new();
while n > 0 {
let rem = n % 5;
let c = match rem {
0 => '0',
1 => '1',
2 => '2',
3 => '=',
4 => '-',
_ => unreachable!(),
};
s.insert(0, c);
n = (n + 2) / 5;
}
s
}
pub fn parse(fh: File) -> Result<impl Iterator<Item = String>> {
Ok(parse::raw_lines(fh))
}
pub fn part1(lines: impl Iterator<Item = String>) -> Result<String> {
Ok(to_snafu(lines.map(from_snafu).sum()))
}
pub fn part2(_: impl Iterator<Item = String>) -> Result<i64> {
todo!()
}
#[test]
fn test() {
assert_eq!(
part1(parse(parse::data(2022, 25).unwrap()).unwrap()).unwrap(),
"2-20=01--0=0=0=2-120"
);
// assert_eq!(
// part2(parse(parse::data(2022, 25).unwrap()).unwrap()).unwrap(),
// 0
// );
}
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