chore(rs): adjust the skeleton

* add data structures as a module with min-heap
* switch ‹.next_vec› to ‹.collect› that also supports other collections
  than ‹Vec<T>›

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

.common/rust/src/main.rs

@@ -2,6 +2,7 @@
 
 // region ‹use›
 use self::aliases::*;
+use self::data_structures::*;
 use self::input::*;
 use self::math::*;
 use self::output::*;
@@ -44,6 +45,38 @@ mod aliases {
     pub type Q<T> = VecDeque<T>;
 }
 
+mod data_structures {
+    use std::cmp::{Ord, Reverse};
+    use std::collections::BinaryHeap;
+
+    #[derive(Debug)]
+    pub struct MinHeap<T> {
+        heap: BinaryHeap<Reverse<T>>,
+    }
+
+    impl<T: Ord> MinHeap<T> {
+        pub fn new() -> MinHeap<T> {
+            MinHeap {
+                heap: BinaryHeap::new(),
+            }
+        }
+
+        pub fn push(&mut self, item: T) {
+            self.heap.push(Reverse(item))
+        }
+
+        pub fn pop(&mut self) -> Option<T> {
+            self.heap.pop().map(|Reverse(x)| x)
+        }
+    }
+
+    impl<T: Ord> Default for MinHeap<T> {
+        fn default() -> Self {
+            Self::new()
+        }
+    }
+}
+
 #[allow(dead_code)]
 mod input {
     use std::collections::VecDeque;
@@ -76,7 +109,7 @@ mod input {
             front.parse::<T>().ok().unwrap()
         }
 
-        pub fn next_vec<T: FromStr>(&mut self, n: usize) -> Vec<T> {
+        pub fn collect<C: FromIterator<T>, T: FromStr>(&mut self, n: usize) -> C {
             (0..n).map(|_| self.next()).collect()
         }
     }