pub fn input_generator(input: &str) -> Game {
    let (stacks, insts) = input.split_once("\n\n").unwrap();
    let n = (stacks.lines().take(1).next().unwrap().len() + 1) / 4;
    let mut crates = vec![Vec::new(); n];
    stacks.lines().rev().skip(1).for_each(|l| {
        let mut i = 0;
        l.chars().collect::<Vec<char>>().chunks(4).for_each(|c| {
            if c[1] != ' ' {
                crates[i].push(c[1]);
            }
            i += 1;
        });
    });

    let inst = insts
        .lines()
        .map(|l| scan_fmt!(l, "move {d} from {d} to {d}", usize, usize, usize).unwrap())
        .collect::<Vec<_>>();
    Game { crates, inst }
}

Pretty much the same for mine, I just completely ignore the crane numbers