refactor: day 8

src/days/d8.rs

@@ -16,13 +16,12 @@ fn _parse (data: &str) -> I {
         let l = l.trim();
         w = l.len();
         for (i, c) in l.chars().enumerate() {
+            if c == '.' { continue; }
             m.entry(c).or_default().push((h as isize, i as isize));
         }
         h += 1;
     }
 
-    m.remove(&'.');
-
     (m, w as isize, h as isize)
 }
 
@@ -48,7 +47,6 @@ fn _solve ((map, width, height): I, n: isize) -> O {
                 let new = [(b.0 + ydiff_mul, b.1 + xdiff_mul), (a.0 - ydiff_mul, a.1 - xdiff_mul)];
 
                 s.extend(new.into_iter().filter(is_valid));
-
             }
         }
     };