Example #1
0
int main(int argc, char* argv[])
{
    int dummy;
    Heap<int> hp;

    hp.Insert(10).Insert(6).Insert(20).Insert(30).Insert(25).Insert(3).Insert(8);
    cout << "Heap elements: " << hp << endl;
    hp.PrintTreeVertically(cout, 64);

    cout << endl << "Heap elements on delete: ";
    while (!hp.IsEmpty()) {
        hp.DeleteMin(dummy);
        cout << dummy << ", ";
    }
    cout << endl;


    // Heap sort
    // In this mechanism/implementation, note that:
    // Descending sort by using Min-Heap, while ascending sort should use Max-Heap
    int a[] = { 1, 3, 4, 2, 5, 9, 3, 6, 7, 9, 4, 8 };
#define ELEM_COUNT(a)   (sizeof(a) / sizeof(a[0]))

    Heap<int>::Sort(a, ELEM_COUNT(a));
    cout << "Sort array descending: ";
    for (int i = 0; i < ELEM_COUNT(a); i++) {
        cout << a[i] << ", ";
    }
    cout << endl;

    return 0;
}
Example #2
0
	void CreateHuffmanTree(const T* array, size_t size, const T& invalid)
	{	
		struct Compare 
		{
			bool operator()(HuffmanNode_P<T>*& lhs, HuffmanNode_P<T>*& rhs)
			{
				return lhs->_weight < rhs->_weight;
			}
		};

		// 1.将所有值构建为节点放入到一个最小堆中,Compare仿函数做比较器
		Heap<HuffmanNode_P<T>*, Compare> minHeap;
		for (int i = 0; i < size; ++i)
		{
			if (array[i] != invalid)
			{
				HuffmanNode_P<T>* node = new HuffmanNode_P<T>(array[i]);
				minHeap.Insert(node);
			}
		}

		if (minHeap.Empty())
			return;

		// 2.获取出最小和次小的节点做孩子节点,并构建这两个孩子节点的父节点进行链接。
		HuffmanNode_P<T>* parent = minHeap.GetHeapTop();
		while (minHeap.Size() > 1)
		{
			HuffmanNode_P<T>* first = minHeap.GetHeapTop();
			minHeap.Remove();
			HuffmanNode_P<T>* second = minHeap.GetHeapTop();
			minHeap.Remove();

			parent = new HuffmanNode_P<T>(first->_weight + second->_weight);
			parent->_left = first;
			parent->_right = second;
			first->_parent = parent;
			second->_parent = parent;

			minHeap.Insert(parent);
		}

		_root = parent;
	}
Example #3
0
	void CreateHuffmanTree(const T* array, size_t size)
	{
		struct Compare 
		{
			bool operator()(const HuffmanNode_A<T>* lhs, const HuffmanNode_A<T>* rhs)
			{
				return lhs->_weight < rhs->_weight;
			}
		};

		// 将节点的指针放入最小堆中,重写比较器
		_vNodes.reserve(size*2 - 1);
		Heap<HuffmanNode_A<T>*, Compare> minHeap;
		size_t index = 0;
		for (; index < size; ++index)
		{
			_vNodes.push_back(HuffmanNode_A<T>(array[index]));
			HuffmanNode_A<T>& node = _vNodes.back();
			node._index = index;
			minHeap.Insert(&node);
		}

		while (minHeap.Size() > 1)
		{
			HuffmanNode_A<T>* first = minHeap.GetHeapTop();
			minHeap.Remove();
			HuffmanNode_A<T>* second = minHeap.GetHeapTop();
			minHeap.Remove();

			_vNodes.push_back(HuffmanNode_A<T>(first->_weight + second->_weight));
			HuffmanNode_A<T>& parent = _vNodes.back();
			parent._index = index++;
			minHeap.Insert(&parent);

			first->_parent = parent._index;
			second->_parent = parent._index;
			parent._left = first->_index;
			parent._right = second->_index;
		}

		_rootIndex = minHeap.GetHeapTop()->_index;
	}
Example #4
0
  void insert(T data){
    if(MaxHeap->size()==0){
      MaxHeap->Insert(data);
      return;
    }

    T maxHeap = MaxHeap->pop();
    T minHeap = MinHeap->pop();

    if(data < maxHeap){
      MaxHeap->Delete();
      MaxHeap->Insert(data);
      swap( maxHeap, data);
    }

    if(MinHeap->size()==0){
      MinHeap->Insert(data);
      return;
    }

    if(data > minHeap){
      MinHeap->Delete();
      MinHeap->Insert(data);
      swap(data,minHeap);
    }

    if(MaxHeap->size() > MinHeap->size())
      MinHeap->Insert(data);
    else
      MaxHeap->Insert(data);
  }
Example #5
0
    int minRefuelStops(int target, int startFuel, vector<vector<int>>& stations) {
        if (startFuel >= target) return 0;

        Heap bfs_q;
        bfs_q.Insert(Stop{-1, startFuel});

        auto n = 0;
        Heap q;
        unordered_map<int, bool> is_added;
        while (!bfs_q.Empty()) {
            auto s = bfs_q.Pop();

            for(auto i = s.index+1; i < stations.size(); ++i) {
                if (s.fuel >= stations[i][0]) {
                    if (is_added.find(i) != is_added.end()) {
                        //continue
                        break;
                    }

                    is_added[i] = true;
                    auto p = Stop{i, stations[i][1] + s.fuel};
                    if (p.fuel >= target) return n+1;
                    q.Insert(p);

                } else {
                    break;
                }
            }

            if (bfs_q.Empty() && !q.Empty()) {
                bfs_q = q;
                n++;
                q.Clear();
                is_added.clear();
            }
        }

        return -1;
    }
Example #6
0
int main() {
    Heap h;

    vector<Stop*> s;

    for (auto i = 0; i < 10; ++i) {
        auto t = new Stop{i+1, i+1};
        s.push_back(t);

        h.Insert(t);
    }


    h.Print();

    vector<Stop*> r;

    h.HeapSort(r);
    for (auto i : r) {
        cout << i->index << endl;
    }

    return 0;
}
// Function implementing algorithm to find median so far.
int getMedian(int e, int &m, Heap &l, Heap &r)
{
    // Are heaps balanced? If yes, sig will be 0
    int sig = Signum(l.GetCount(), r.GetCount());
    switch(sig)
    {
    case 1: // There are more elements in left (max) heap
 
        if( e < m ) // current element fits in left (max) heap
        {
            // Remore top element from left heap and
            // insert into right heap
            r.Insert(l.ExtractTop());
 
            // current element fits in left (max) heap
            l.Insert(e);
        }
        else
        {
            // current element fits in right (min) heap
            r.Insert(e);
        }
 
        // Both heaps are balanced
        m = Average(l.GetTop(), r.GetTop());
 
        break;
 
    case 0: // The left and right heaps contain same number of elements
 
        if( e < m ) // current element fits in left (max) heap
        {
            l.Insert(e);
            m = l.GetTop();
        }
        else
        {
            // current element fits in right (min) heap
            r.Insert(e);
            m = r.GetTop();
        }
 
        break;
 
    case -1: // There are more elements in right (min) heap
 
        if( e < m ) // current element fits in left (max) heap
        {
            l.Insert(e);
        }
        else
        {
            // Remove top element from right heap and
            // insert into left heap
            l.Insert(r.ExtractTop());
 
            // current element fits in right (min) heap
            r.Insert(e);
        }
 
        // Both heaps are balanced
        m = Average(l.GetTop(), r.GetTop());
 
        break;
    }
 
    // No need to return, m already updated
    return m;
}