LearningCPP/main.cpp

#include <iostream>
#include <iomanip>

using string = std::string;

//Place in header!
template <typename T>
void printm(T m){
  std::cout << m;
}

template <typename T>
void printlm(T m){
  printm(m);
  printm("\n");
}

class Heap {
  int pos {0};
  int length {0};
  int size;
  int* storage;
public:
  Heap(int sz) {
    size = sz;
    storage = new int[sz];
  }
  ~Heap() {
    delete[] storage;
  }
  bool isEmpty() {
    return length == 0;
  }
  void add(int item) {
    if (length + 1 > size) return;
    pos = length;
    while (pos > 0 && storage[(pos-1)/2] < item) {
      storage[pos] = storage[(pos-1)/2];
      pos = (pos-1)/2;
    }
    storage[pos] = item;
    ++length;
  }
  int extractMax() {
    int max {storage[0]};
    storage[0] = storage[--length];
    int first {0};
    while ((2*first)+1 <= length - 1) {
      int largest {(2*first)+1};
      if ((2*first)+2 <= length - 1 && storage[largest] < storage[(2*first)+2]) largest = (2*first)+2;
      if (storage[first] >= storage[largest]) break;
      int swap = storage[first];
      storage[first] = storage[largest];
      storage[largest] = swap;
      first = largest;
    }
    return max;
  }
};

int prompti(string,bool*);

int main() {
  printlm("Create Heap:");
  Heap h{16};
  bool s {};
  int i {0};
  do {
    auto d = prompti("Enter a number: ",&s);
    if (s) {
      h.add(d);
      ++i;
    }
  }
  while(s && i < 16);
  printlm("Output Heap:");
  while (!h.isEmpty()) printlm(h.extractMax());
  return 0;
}

int prompti(string message, bool *status) {
  int tr {};
  *status = false;
  std::cout << message;
  if (!(std::cin >> tr)){
    std::cin.clear();
    std::cin.ignore();
    return 0;
  }
  *status = true;
  return tr;
}