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#![allow(dead_code)]
#![allow(unused_variables)]
use advent_of_code::prelude::*;
pub struct Map {
grid: Grid<u8>,
start: (Row, Col),
end: (Row, Col),
}
impl advent_of_code::graph::Graph<(Row, Col), (Row, Col)> for Map {
type Edges = advent_of_code::grid::Adjacent;
fn edges(&self, v: (Row, Col)) -> Self::Edges {
self.grid.adjacent(v.0, v.1, false)
}
fn edge(&self, v: (Row, Col), e: (Row, Col)) -> ((Row, Col), u64) {
(
e,
if self.grid[e.0][e.1] >= self.grid[v.0][v.1].saturating_sub(1) {
1
} else {
(self.grid.rows().0 * self.grid.cols().0)
.try_into()
.unwrap()
},
)
}
}
pub fn parse(fh: File) -> Result<Map> {
let mut start = None;
let mut end = None;
let grid = parse::grid(parse::raw_lines(fh), |c, row, col| match c {
b'a'..=b'z' => c - b'a',
b'S' => {
start = Some((row, col));
0
}
b'E' => {
end = Some((row, col));
b'z' - b'a'
}
_ => panic!("unknown map char '{c}'"),
});
Ok(Map {
grid,
start: start.expect("start not found"),
end: end.expect("end not found"),
})
}
pub fn part1(map: Map) -> Result<u64> {
Ok(map.dijkstra(map.end, |v| v == map.start).0)
}
pub fn part2(map: Map) -> Result<u64> {
Ok(map.dijkstra(map.end, |v| map.grid[v.0][v.1] == 0).0)
}
#[test]
fn test() {
assert_eq!(
part1(parse(parse::data(2022, 12).unwrap()).unwrap()).unwrap(),
504
);
assert_eq!(
part2(parse(parse::data(2022, 12).unwrap()).unwrap()).unwrap(),
500
);
}
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