chore(rs): refactor reading ‹Vec<T>›

Signed-off-by: Matej Focko <me@mfocko.xyz>

.common/rust/src/main.rs

@@ -288,13 +288,7 @@ mod input {
         }
 
         pub fn next_vec<T: FromStr>(&mut self, n: usize) -> Vec<T> {
-            let mut arr = vec![];
-
-            for _ in 0..n {
-                arr.push(self.next::<T>());
-            }
-
-            arr
+            (0..n).map(|_| self.next()).collect()
         }
     }
 }