bendns' repos / aoc
heh
Diffstat (limited to 'src/util.rs')
-rw-r--r--src/util.rs20
1 files changed, 20 insertions, 0 deletions
diff --git a/src/util.rs b/src/util.rs
index 04e0415..bb4309f 100644
--- a/src/util.rs
+++ b/src/util.rs
@@ -223,6 +223,14 @@ impl Dir {
x => unreachable!("{}", x as char),
}
}
+ pub fn add_1(self) -> Self {
+ use Dir::*;
+ unsafe { std::mem::transmute((self as u8 + 1) % 4) }
+ }
+ pub fn sub_1(self) -> Self {
+ use Dir::*;
+ unsafe { std::mem::transmute(((self as u8).wrapping_sub(1)) % 4) }
+ }
pub fn turdl(self) -> u8 {
match self {
Self::N => b'U',
@@ -1958,11 +1966,15 @@ pub fn countmap<T: Hash + Eq + Ord + Copy>(
pub trait MapWith<T: Copy> {
fn map_w<U>(self, f: impl FnMut(T) -> U) -> impl Iterator<Item = (T, U)>;
+ fn fmap_w<U>(self, f: impl FnMut(T) -> Option<U>) -> impl Iterator<Item = (T, U)>;
}
impl<T: Copy, I: Iterator<Item = T>> MapWith<T> for I {
fn map_w<U>(self, mut f: impl FnMut(T) -> U) -> impl Iterator<Item = (T, U)> {
self.map(move |x| (x, f(x)))
}
+ fn fmap_w<U>(self, mut f: impl FnMut(T) -> Option<U>) -> impl Iterator<Item = (T, U)> {
+ self.flat_map(move |x| Some(x).zip(f(x)))
+ }
}
pub fn md5(x: &[u8]) -> [u8; 16] {
@@ -2026,6 +2038,14 @@ impl<const N: usize, const M: usize> GridFind for [[u8; N]; M] {
(i % N, i / N)
}
}
+impl GridFind for &[&[u8]] {
+ fn find(self, c: u8) -> (usize, usize) {
+ self.iter()
+ .zip(0..)
+ .find_map(|(x, y)| x.iter().position(|&x| x == c).map(|x| (x, y)))
+ .unwrap()
+ }
+}
pub trait TwoWayMapCollect<K, V>: Iterator {
fn collect_twm(self) -> HashMap<(K, K), V>;