day08: Adapt code for part 2

I could probably optimize that by getting the iterators for all 4
directions and then to the scan on each of them in a loop, but I'm with
with this right now.
This commit is contained in:
MasterofJOKers 2022-12-20 23:48:03 +01:00
parent 30c0c2b42f
commit 2ffa87d872
1 changed files with 36 additions and 7 deletions

View File

@ -19,29 +19,57 @@ fn main() -> Result<(), Box<dyn error::Error>> {
let width = width;
let height = map.len() / width;
let mut visible_count = 0;
let mut scenic_scores = vec![];
for i in 0..map.len() {
let line = i / height;
let column = i % width + 1; // we need + 1 here, because there is no modulo 0
let mut scenic_score = 1;
// tree-houses cannot be built on the outside, so we have to skip those outside-trees for
// the calculation
if line == 0 || line == height - 1 || column == 1 || column == width {
continue;
}
// println!("line: {}, column: {}, self: {}", line, column, map[i]);
let left = map[(line * width)..i].iter().max();
let left = map[(line * width)..i].iter()
.rev()
.scan(true, |state, &x| if !*state { None } else { if x >= map[i] { *state = false }; Some(1) })
// .inspect(|x| println!("{x}"))
.count();
if left > 0 {
scenic_score *= left;
}
let right = map[i..((line + 1) * width)].iter()
.enumerate()
.filter_map(|(j, x)| if (j + i) / height == line && j > 0 { Some(x) } else { None })
.max();
.scan(true, |state, &x| if !*state { None } else { if x >= map[i] { *state = false }; Some(1) })
.count();
if right > 0 {
scenic_score *= right;
}
// let right = map[(i + 1)..((line + 1) * width)].iter().max();
let up = map[0..i].iter()
.enumerate()
//.inspect(|(j, x)| println!("{j} {x}"))
.filter_map(|(j, x)| if (j + 1) % width == column { Some(x) } else { None })
.max();
.rev()
.scan(true, |state, &x| if !*state { None } else { if x >= map[i] { *state = false }; Some(1) })
.count();
if up > 0 {
scenic_score *= up;
}
let down = map[i..].iter()
.enumerate()
.filter_map(|(j, x)| if (i + j + 1) % width == column && j > 0 { Some(x) } else { None })
.max();
.scan(true, |state, &x| if !*state { None } else { if x >= map[i] { *state = false }; Some(1) })
.count();
if down > 0 {
scenic_score *= down;
}
// println!("left: {:?}, right: {:?}, up: {:?}, down: {:?}", &left, &right, &up, &down);
/*
for direction_max in vec![left, right, up, down] {
match direction_max {
Some(x) if x < &map[i] => {
@ -55,9 +83,10 @@ fn main() -> Result<(), Box<dyn error::Error>> {
_ => ()
}
}
// println!("visible: {visible_count}");
*/
scenic_scores.push(scenic_score);
}
println!("Found {visible_count} visible trees.");
println!("Highest scenic score is {}", scenic_scores.iter().max().unwrap_or(&0));
Ok(())
}