How do I implement a heap in C++?

How do I implement a heap in C++?

To implement a heap in C++, you can use a vector to store the elements and maintain the heap property.

What are the differences between a max heap and a min heap?

A max heap ensures that the parent node is greater than or equal to its children, while a min heap does the opposite.

Can you show me a simple code example for a max heap?

Sure! Here's a basic implementation:

#include <vector>
#include <iostream>

class MaxHeap {
private:
    std::vector<int> heap;

    void heapifyUp(int index) {
        while (index > 0 && heap[parent(index)] < heap[index]) {
            std::swap(heap[parent(index)], heap[index]);
            index = parent(index);
        }
    }

    int parent(int index) { return (index - 1) / 2; }

public:
    void insert(int value) {
        heap.push_back(value);
        heapifyUp(heap.size() - 1);
    }

    void printHeap() {
        for (int val : heap) {
            std::cout << val << " ";
        }
        std::cout << std::endl;
    }
};

int main() {
    MaxHeap maxHeap;
    maxHeap.insert(10);
    maxHeap.insert(20);
    maxHeap.insert(15);
    maxHeap.printHeap(); // Output: 20 10 15
}

How do I remove the maximum element from the heap?

To remove the maximum element, swap the root with the last element, pop the last element, and then heapify down from the root.