D2

D2.cpp

@@ -0,0 +1,173 @@
+#include <iostream>
+#include <algorithm>
+#include <cstring>
+
+class Heap{
+ private:
+  long long *buffer;
+  long long *node;
+  long long *point;
+  long long buffer_size;
+  long long size_two;
+  long long size;
+  long long iter;
+  void GrowQuery();
+  void GrowBuffer();
+  void SiftUp(long long v);
+  void SiftDown(long long v);
+ public:
+  Heap(){
+    size_two = 1000;
+    iter = 0;
+    node = new long long[size_two];
+    point = new long long[size_two];
+    buffer_size = 1000;
+    size = 0;
+    buffer = new long long[buffer_size];
+  }
+  ~Heap(){
+    delete[] point;
+    delete[] node;
+    delete[] buffer;
+  }
+  void Insert(long long x);
+  long long GetMin();
+  void ExtractMin();
+  void DecreaseKey(long long i, long long delta);
+};
+
+void Heap::DecreaseKey(long long i, long long delta) {
+  if (iter + 1 >= size_two){
+    GrowQuery();
+  }
+  iter++;
+  long long bolt = point[i];
+  buffer[bolt] = buffer[bolt] - delta;
+  SiftUp(bolt);
+}
+
+void Heap::GrowQuery() {
+  size_two = size_two * 2;
+  auto* new_node = new long long[size_two];
+  auto* new_point = new long long[size_two];
+  memcpy(new_node, node, (iter + 1) * sizeof(long long));
+  memcpy(new_point, point, (iter + 1) * sizeof(long long));
+  delete[] node;
+  delete[] point;
+  node = new_node;
+  point = new_point;
+}
+
+void Heap::GrowBuffer() {
+  buffer_size = buffer_size * 2;
+  auto* new_buffer = new long long[buffer_size];
+  std::memcpy(new_buffer, buffer, (size+1)* sizeof(long long));
+  delete[] buffer;
+  buffer = new_buffer;
+}
+
+void Heap::SiftDown(long long v) {
+  while (2 * v <= size) {
+    long long u = 2 * v;
+    if (((u+1) <= size) and (buffer[u+1] < buffer[u])) {
+      u++;
+    }
+    if (buffer[u] < buffer[v]) {
+      long long first = node[u];
+      long long second = node[v];
+      point[first] = v;
+      point[second] = u;
+      node[u] = second;
+      node[v] = first;
+      std::swap(buffer[u], buffer[v]);
+      v = u;
+    }
+    else break;
+  }
+}
+
+void Heap::SiftUp(long long v) {
+  while(v >= 2) {
+    if (buffer[v] < buffer[v/2]) {
+      long long first = node[v];
+      long long second = node[v/2];
+      point[first] = v/2;
+      point[second] = v;
+      node[v] = second;
+      node[v/2] = first;
+      std::swap(buffer[v], buffer[v/2]);
+      v/=2;
+    }
+    else break;
+  }
+}
+
+void Heap::Insert(long long x) {
+  if (size + 2 > buffer_size){
+    GrowBuffer();
+  }
+  if (iter + 2 > size_two) {
+    GrowQuery();
+  }
+  size++;
+  iter++;
+  buffer[size] = x;
+  point[iter] = size;
+  node[size] = iter;
+  SiftUp(size);
+}
+
+long long Heap::GetMin() {
+  if (iter + 2 > size_two) {
+    GrowQuery();
+  }
+  iter++;
+  return buffer[1];
+}
+
+void Heap::ExtractMin() {
+  if (iter + 1 >= size_two) {
+    GrowQuery();
+  }
+  iter++;
+  long long first = node[1];
+  long long second = node[size];
+  point[first] = size;
+  point[second] = 1;
+  node[1] = second;
+  node[size] = first;
+  std::swap(buffer[1], buffer[size]);
+  //buffer[size] = 1e10;
+  size--;
+  SiftDown(1);
+}
+
+int main() {
+  std::ios_base::sync_with_stdio(false);
+  std::cin.tie(nullptr); std::cout.tie(nullptr);
+  int q;
+  std::cin >> q;
+  Heap lol;
+  while(q--) {
+    std::string s;
+    std::cin >> s;
+    if (s == "insert") {
+      long long x;
+      std::cin >> x;
+      lol.Insert(x);
+    }
+    if (s == "getMin") {
+      std::cout << lol.GetMin() << "\n";
+    }
+    if (s == "extractMin") {
+      lol.ExtractMin();
+    }
+    if (s == "decreaseKey") {
+      long long i;
+      long long triangle;
+      std::cin >> i >> triangle;
+      lol.DecreaseKey(i, triangle);
+    }
+  }
+  return 0;
+}