bert/adventofcode
1
0
Fork 0
mirror of https://github.com/bertptrs/adventofcode.git synced 2025-12-25 21:00:31 +01:00
Code Issues Projects Releases Wiki Activity

Day 20: faster monster finding by looking upside down

Browse Source
This commit is contained in:
Bert Peters
2020-12-20 19:58:51 +01:00
parent 68c8b1915d
commit 3a993419fc
2 changed files with 24 additions and 11 deletions
Download Patch File Download Diff File Expand all files Collapse all files

33
2020/src/day20.rs
View File

@@ -339,6 +339,23 @@ fn replace_monster(image: &mut [Vec<u8>]) {
}
})
});
} else if searchers[2].is_match(&image[i - 1][range.clone()])
&& searchers[0].is_match(&image[i + 1][range.clone()])
{
image[(i - 1)..=(i + 1)]
.iter_mut()
.rev()
.zip(&searchers)
.for_each(|(line, expr)| {
line[range.clone()]
.iter_mut()
.zip(expr.as_str().as_bytes().iter())
.for_each(|(b, &r)| {
if *b == r {
*b = b'O';
}
})
});
}
}
}
@@ -369,17 +386,13 @@ impl Solution for Day20 {
let mut image = combine_tiles(&rows, &mut tiles);
for _ in 0..4 {
replace_monster(&mut image);
image = rotate(&image);
}
replace_monster(&mut image);
reverse(&mut image);
for _ in 0..4 {
replace_monster(&mut image);
image = rotate(&image);
}
replace_monster(&mut image);
image = rotate(&image);
replace_monster(&mut image);
reverse(&mut image);
replace_monster(&mut image);
image
.iter()