#[path = "../lib.rs"] mod lib;

fn get_int(line: &str, i: usize) -> Option<usize> {
    let s = line.split(' ').nth(i)?;
    return s.parse::<usize>().ok();
}

fn run(label: &str, reverse: bool) {
    let mut stacks: Vec<Vec<char>> = vec![];
    let mut init = false;

    for line in lib::iter_input() {
        if !init {
            if line.len() == 0 {
                init = true;
            } else {
                while stacks.len() * 4 < line.len() + 1 {
                    stacks.push(vec![]);
                }
                for i in 0..stacks.len() {
                    let c = line.chars().nth(i * 4 + 1).unwrap();
                    if c != ' ' {
                        stacks[i].insert(0, c);
                    }
                }
            }
        } else {
            let k = get_int(&line, 1).unwrap();
            let a = get_int(&line, 3).unwrap();
            let b = get_int(&line, 5).unwrap();

            if reverse {
                for _ in 0..k {
                    let c = stacks[a - 1].pop().unwrap();
                    stacks[b - 1].push(c);
                }
            } else {
                let mut tmp = vec![];

                for _ in 0..k {
                    let c = stacks[a - 1].pop().unwrap();
                    tmp.push(c);
                }

                while tmp.len() > 0 {
                    let c = tmp.pop().unwrap();
                    stacks[b - 1].push(c);
                }
            }
        }
    }

    print!("{}: ", label);
    for stack in stacks {
        print!("{}", stack.last().unwrap());
    }
    print!("\n");
}

fn main() {
    run("part1", true);
    run("part2", false);
}