upload

3/D.cpp

@@ -0,0 +1,85 @@
+#include <iostream>
+
+struct Node {
+  Node* next;
+  Node* prev;
+  int weight;
+};
+
+class Backpack {
+ private:
+  Node* first = nullptr;
+  Node* last = nullptr;
+  int count = 0;
+ public:
+  void Add(int weight) {
+    Node* new_node = new Node {nullptr, last, weight};
+    if (count == 0) {
+      first = new_node;
+      last = new_node;
+    } else {
+      last->next = new_node;
+      last = new_node;
+    }
+    ++count;
+  }
+  int PopFirst() {
+    if (count != 0) {
+      Node* prev = first;
+      int weight = first->weight;
+      first = first->next;
+      --count;
+      delete prev;
+      return weight;
+    }
+  }
+
+  int PopLast() {
+    if (count != 0) {
+      Node* prev = last;
+      int weight = last->weight;
+      last = last->prev;
+      --count;
+      delete prev;
+      return weight;
+    }
+  }
+};
+
+int main() {
+  int n, max_count;
+  std::cin >> n >> max_count;
+  Backpack bp;
+
+  if (n <= max_count) {
+    int x;
+    while (std::cin >> x) {
+      std::cout << x << ' ';
+    }
+    return 0;
+  }
+
+  for (int i = 0; i < n; ++i) {
+    int x;
+    std::cin >> x;
+
+    if (i >= max_count) {
+      int y = bp.PopLast();
+      int z = bp.PopFirst();
+      if (x < y)
+        std::swap(x, y);
+      if (y < z)
+        std::swap(y, z);
+      if (x < y)
+        std::swap(x, y);
+      bp.Add(y);
+    }
+    bp.Add(x);
+  }
+
+  for (int i = 0; i < max_count; ++i) {
+    std::cout << bp.PopFirst() << ' ';
+  }
+
+  return 0;
+}