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fn main() {
let input = lib::read_input(8);
part1(&input);
part2(&input);
}
fn part1(input: &str) {
let input = input.split_whitespace().map(|x| x.bytes().collect::<Vec<_>>()).collect::<Vec<_>>();
let mut ans = 0;
for (y, line) in input.iter().enumerate() {
for (x, _) in line.iter().enumerate() {
if visible(&input, x, y) {
ans += 1;
}
}
}
println!("{}", ans);
}
fn part2(input: &str) {
let input = input.split_whitespace().map(|x| x.bytes().collect::<Vec<_>>()).collect::<Vec<_>>();
let mut ans = 0;
for (y, line) in input.iter().enumerate() {
for (x, _) in line.iter().enumerate() {
ans = ans.max(scenic_score(&input, x, y));
}
}
println!("{}", ans);
}
fn scenic_score(heights: &[Vec<u8>], x: usize, y: usize) -> u32 {
let mut score = 1;
for (dy, dx) in &[(0, 1), (0, -1), (1, 0), (-1, 0)] {
let height = heights[y][x];
let mut seen = 0;
let mut sx = x as i32;
let mut sy = y as i32;
loop {
sx += dx;
sy += dy;
if sx < 0 || sy < 0 || sy >= heights.len() as i32 || sx >= heights[sy as usize].len() as i32 {
break;
}
seen += 1;
if heights[sy as usize][sx as usize] >= height {
break;
}
}
score *= seen;
}
score
}
fn visible(heights: &[Vec<u8>], x: usize, y: usize) -> bool {
for (dy, dx) in &[(0, 1), (0, -1), (1, 0), (-1, 0)] {
let height = heights[y][x];
let mut sx = x as i32;
let mut sy = y as i32;
loop {
sx += dx;
sy += dy;
if sx < 0 || sy < 0 || sx >= heights[0].len() as i32 || sy >= heights.len() as i32 {
return true;
}
if heights[sy as usize][sx as usize] >= height {
break;
}
}
}
return false;
}
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