用最大堆实现优先队列（c++）

#include <iostream>
#include <vector>
using namespace std;

template<typename T>
class PriorityQueue {
private:
vector<T> v;
int size;
const static int initCap = 100;
private:
int parent(int pos) {
return pos/2;
}

int left(int pos) {
return pos*2;
}

int right(int pos) {
return pos*2 + 1;
}
public:
PriorityQueue():
size(0) {
v = vector<T>(initCap);
}

bool enQueue(const T& t) {
size++;
v[size] = t;
int i = size;
//插入到尾部，一直上提到使当前堆符合最大堆性质为止
while(i > 1 && v[i] > v[parent(i)]) {
T tmp = v[i];
v[i] = v[parent(i)];
v[parent(i)] = tmp;
i = parent(i);
}
return true;
}

bool deQueue(T& max) {
//取出最大值，并把尾部元素和最大值交换，然后维护当前堆到符合堆性质
if(size < 1) {
return false;
}
max = v[1];
v[1] = v[size];
v[size] = max;
size--;
maxHeapIfy(1);
return true;
}

void maxHeapIfy(int pos) {
int largestPos = pos;
if(left(pos) <= size && v[pos] < v[left(pos)]) {
largestPos = left(pos);
}
if(right(pos) <= size && v[largestPos] < v[right(pos)]) {
largestPos = right(pos);
}
if(largestPos != pos) {
T tmp = v[pos];
v[pos] = v[largestPos];
v[largestPos] = tmp;
maxHeapIfy(largestPos);
}
}

int getSize() {
return size;
}

bool top(T& t) {
if(size < 1) {
return false;
}
t = v[1];
return true;
}
};

int main() {
PriorityQueue<int> pQ;
pQ.enQueue(8);
pQ.enQueue(1);
pQ.enQueue(3);
pQ.enQueue(6);
pQ.enQueue(5);
pQ.enQueue(3);
pQ.enQueue(10);
pQ.enQueue(9);
pQ.enQueue(7);
int a = -1;
while(pQ.deQueue(a)) {
cout<<a<<" ";
}
cout<<endl;
return 0;
}