最大堆实现优先队列

头文件

#include "heap_sort.h"
#include "stdexcept"
#include <iostream>
class MaxHeapPriorityQueue {
public:int heap_size;
private:int capacity;int *array;void increase_key(int key,int index);
public:void insert(int key);int maximum();int extract_max();void heap_delete(int index);const int* get_array();MaxHeapPriorityQueue(int capacity = 50);MaxHeapPriorityQueue(const int *array,const int length);virtual ~MaxHeapPriorityQueue();
};

cpp文件

#include "MaxHeapPriorityQueue.h"
MaxHeapPriorityQueue::MaxHeapPriorityQueue(int capacity):capacity(capacity)
{array = new int [capacity];heap_size = 0;
}
MaxHeapPriorityQueue::MaxHeapPriorityQueue(const int *array,const int length)
{capacity = length;this->array = new int [capacity];heap_size = capacity;for (int i = 0; i < heap_size; ++i) {this->array[i] = array[i];}build_heap(this->array,heap_size);
}
void MaxHeapPriorityQueue::increase_key(int key,int index){if(index >= heap_size || key < array[index]){perror("new key error");return;}array[index] = key;while (index>0 && array[parent(index)] < key){array[index] = array[parent(index)];array[parent(index)] = key;index = parent(index);}}
void MaxHeapPriorityQueue::insert(int key){heap_size ++;if(heap_size>capacity){int *temp_array = new int [capacity*2];for (int i = 0; i < heap_size; ++i) {temp_array[i] = array[i];}delete[] array;array = temp_array;capacity *= 2;}array[heap_size - 1] = INT_MIN;increase_key(key,heap_size-1);}
int MaxHeapPriorityQueue::maximum(){return array[0];
}
int MaxHeapPriorityQueue::extract_max(){int max = array[0];array[0] = array[heap_size-1];heap_size --;max_heapify(array,heap_size,0);return max;
}void MaxHeapPriorityQueue::heap_delete(int index){if(index>=heap_size || index < 0 || heap_size<=0){perror("index overflow");return;}if(array[index] > array[heap_size-1]){array[index] = array[heap_size-1];max_heapify(array,heap_size-1,index);}else{increase_key(array[heap_size-1],index);}heap_size --;
}
const int* MaxHeapPriorityQueue::get_array(){return  array;
}
MaxHeapPriorityQueue::~MaxHeapPriorityQueue()
{if(array!= nullptr)delete [] array;
}