grid: add rotated/mirrored

README.md

@@ -1,6 +1,6 @@
 <!-- AOC TILES BEGIN -->
 <h1 align="center">
-  2025 - 20 ⭐ - Rust
+  2025 - 21 ⭐ - Rust
 </h1>
 <a href="src/day1.rs">
   <img src=".aoc_tiles/tiles/2025/01.png" width="161px">
@@ -35,4 +35,7 @@
 <a href="src/day11.rs">
   <img src=".aoc_tiles/tiles/2025/11.png" width="161px">
 </a>
+<a href="src/day12.rs">
+  <img src=".aoc_tiles/tiles/2025/12.png" width="161px">
+</a>
 <!-- AOC TILES END -->

utils/grid/lib.rs

@@ -22,6 +22,11 @@ pub const ADJACENT_OFFSETS: [&(i64, i64); 8] = [
 /// NESW
 pub const CARDINAL_OFFSETS: [&(i64, i64); 4] = [&(0, -1), &(-1, 0), &(1, 0), &(0, 1)];
 
+pub enum MirrorAxis {
+    X,
+    Y,
+}
+
 #[derive(Copy, Clone, Eq, PartialEq, Ord, PartialOrd, Hash, Debug)]
 pub struct Coord2d {
     pub x: i64,
@@ -281,7 +286,7 @@ impl<'a, T: Clone + Eq + PartialEq + Debug> Iterator for OffsetsIter<'a, T> {
     }
 }
 
-#[derive(Clone, Eq, PartialEq, Debug)]
+#[derive(Clone, Eq, PartialEq, Debug, Hash)]
 pub struct Grid<T> {
     pub data: Vec<T>,
     width: i64,
@@ -486,6 +491,79 @@ impl<T: Clone + Eq + PartialEq + Debug> Grid<T> {
         }
     }
 
+    pub fn rotated(&self, mut rot: u8) -> Self {
+        rot %= 4;
+        match rot {
+            0 => self.clone(),
+            1 => {
+                let mut n = Grid::with_shape(self.height(), self.width(), self.data[0].clone()); // fill will be overwritten anyway
+                for y in 0..self.height() {
+                    for x in 0..self.width() {
+                        n.set(
+                            &(self.height() - y - 1, x),
+                            self.get(&(x as u64, y as u64)).unwrap().clone(),
+                        );
+                    }
+                }
+                n
+            }
+            2 => {
+                let mut n = Grid::with_shape(self.height(), self.width(), self.data[0].clone()); // fill will be overwritten anyway
+                for y in 0..self.height() {
+                    for x in 0..self.width() {
+                        n.set(
+                            &(self.width() - x - 1, self.height() - y - 1),
+                            self.get(&(x as u64, y as u64)).unwrap().clone(),
+                        );
+                    }
+                }
+                n
+            }
+            3 => {
+                let mut n = Grid::with_shape(self.height(), self.width(), self.data[0].clone()); // fill will be overwritten anyway
+                for y in 0..self.height() {
+                    for x in 0..self.width() {
+                        n.set(
+                            &(self.height() - y - 1, self.width() - x - 1),
+                            self.get(&(x as u64, y as u64)).unwrap().clone(),
+                        );
+                    }
+                }
+                n
+            }
+            _ => unreachable!("invalid rotation"),
+        }
+    }
+
+    pub fn mirrored(&self, axis: MirrorAxis) -> Self {
+        match axis {
+            MirrorAxis::X => {
+                let mut n = Grid::with_shape(self.height(), self.width(), self.data[0].clone()); // fill will be overwritten anyway
+                for y in 0..self.height() {
+                    for x in 0..self.width() {
+                        n.set(
+                            &(self.width() - x - 1, y),
+                            self.get(&(x as u64, y as u64)).unwrap().clone(),
+                        );
+                    }
+                }
+                n
+            }
+            MirrorAxis::Y => {
+                let mut n = Grid::with_shape(self.height(), self.width(), self.data[0].clone()); // fill will be overwritten anyway
+                for y in 0..self.height() {
+                    for x in 0..self.width() {
+                        n.set(
+                            &(x, &self.height() - y - 1),
+                            self.get(&(x as u64, y as u64)).unwrap().clone(),
+                        );
+                    }
+                }
+                n
+            }
+        }
+    }
+
     // fn window_compare_impl<const REV: bool>(&self, needle: &[T]) -> Vec<(i64, i64)> {
     //     if (self.width as usize) < needle.len() {
     //         return Vec::new();