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use std::cmp::max;
mod common;
use common::*;
#[derive(Copy, Clone, Debug)]
pub struct Position {
pub i: usize,
pub j: usize,
pub d: Direction
}
pub struct Map {
pub tiles: Vec<Vec<Tile>>
}
type StepFn = fn(&Map, Position) -> Position;
impl Map {
pub fn from_stdin() -> Map {
let mut maxlen = 0;
let mut tiles = vec![];
let mut line = String::new();
while std::io::stdin().read_line(&mut line).unwrap() > 1 {
let v = line[0..line.len()-1].as_bytes().iter()
.map(|b| Tile::from_byte(*b)).collect::<Vec<_>>();
maxlen = max(maxlen, v.len());
tiles.push(v);
line.clear();
}
for v in &mut tiles {
while v.len() < maxlen { v.push(Tile::Skip); }
}
Map { tiles }
}
pub fn start_position(&self) -> Position {
let first_valid = self.tiles[0].iter()
.position(|t| *t == Tile::Walk).unwrap();
Position { i: 0, j: first_valid, d: Direction::Right }
}
pub fn walk(&self, pos: Position, n: usize, step: StepFn) -> Position {
let mut p = pos;
for _ in 0..n { p = step(self, p); }
p
}
}
fn step(map: &Map, position: Position) -> Position {
let imax = map.tiles.len();
let jmax = map.tiles[0].len();
let s = position.d.step();
let mut p = position;
loop {
let inext = ((s.0 + imax as i64) as usize + p.i) % imax;
let jnext = ((s.1 + jmax as i64) as usize + p.j) % jmax;
p = Position { i: inext, j: jnext, d: p.d };
match map.tiles[p.i][p.j] {
Tile::Walk => return p,
Tile::Wall => return position,
Tile::Skip => ()
}
}
}
fn password(p: Position) -> usize {
1000 * (p.i+1) + 4 * (p.j+1) + p.d.value()
}
fn main() {
let map = Map::from_stdin();
let (turns, steps) = read_instruction_line_from_stdin();
let mut position = map.start_position();
for i in 0..turns.len() {
position = map.walk(position, steps[i], step);
position.d = position.d.turn(turns[i]);
}
position = map.walk(position, steps[steps.len()-1], step);
println!("{}", password(position));
}
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