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use std::io;
fn main() -> io::Result<()> {
let grid = io::stdin()
.lines()
.flatten()
.map(|line| line.chars().collect())
.collect::<Vec<Vec<char>>>();
let grid = Grid(grid);
let silver: usize = silver(&grid);
let gold: usize = gold(&grid);
println!("silver: {silver}");
println!("gold: {gold}");
return Ok(());
}
struct Grid(Vec<Vec<char>>);
impl Grid {
fn at(&self, (x, y): (isize, isize)) -> Option<&char> {
self.0
.get(usize::try_from(y).ok()?)?
.get(usize::try_from(x).ok()?)
}
fn check<'a>(
&self,
(x, y): (isize, isize),
mut pat: impl Iterator<Item = &'a ((isize, isize), char)>,
) -> bool {
pat.all(|((dx, dy), ch)| self.at((x + dx, y + dy)).is_some_and(|c| c == ch))
}
fn pts(&self) -> impl Iterator<Item = (isize, isize)> + use<'_> {
(0..self.0[0].len()).flat_map(|x| (0..self.0.len()).map(move |y| (x as isize, y as isize)))
}
}
fn silver(grid: &Grid) -> usize {
let dirs = vec![
(-1, -1),
(-1, 0),
(-1, 1),
(0, -1),
(0, 1),
(1, -1),
(1, 0),
(1, 1),
];
let xmases: Vec<Vec<((isize, isize), char)>> = dirs
.iter()
.map(|(dx, dy)| {
(0..4)
.map(move |n| (dx * n, dy * n))
.zip("XMAS".chars())
.collect()
})
.collect();
grid.pts()
.flat_map(|p| xmases.iter().map(move |xmas| grid.check(p, xmas.iter())))
.filter(|p| *p)
.count()
}
fn gold(grid: &Grid) -> usize {
let dirs = vec![(-1, -1), (1, -1), (0, 0), (-1, 1), (1, 1)];
let xmases: Vec<Vec<((isize, isize), char)>> = vec!["MMASS", "SMASM", "SSAMM", "MSAMS"]
.iter()
.map(|x| dirs.clone().into_iter().zip(x.chars()).collect())
.collect();
grid.pts()
.flat_map(|p| xmases.iter().map(move |xmas| grid.check(p, xmas.iter())))
.filter(|p| *p)
.count()
}
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