Day t/m 6p1 done

advent_of_code_2024/src/day4/part2.rs

@@ -0,0 +1,27 @@
+pub fn solve(input: &str) {
+    let grid = input.lines().map(|str| str.as_bytes()).collect::<Vec<_>>();
+    let width = grid[0].len() as i32;
+    let height = grid.len() as i32;
+    let words = ((b'M', b'A', b'S'), (b'S', b'A', b'M'));
+
+    let mut matches = 0;
+
+    for xpos in 1..(width - 1) {
+        for ypos in 1..(height - 1) {
+            if grid[xpos as usize][ypos as usize] == b'A' {
+                let left = (grid[(xpos - 1) as usize][(ypos - 1) as usize],
+                            grid[(xpos) as usize][(ypos) as usize],
+                            grid[(xpos + 1) as usize][(ypos + 1) as usize]);
+                let right = (grid[(xpos + 1) as usize][(ypos - 1) as usize],
+                             grid[(xpos) as usize][(ypos) as usize],
+                             grid[(xpos - 1) as usize][(ypos + 1) as usize]);
+                
+                if (left == words.0 || left == words.1) && (right == words.0 || right == words.1) {
+                    matches += 1;
+                }
+            }
+        }
+    }
+
+    println!("matches: {}", matches);
+}