在C++中使用向量实现简单优先级队列

Question

以下给出了下面提到的代码的错误.哪里出错了？

error: ‘function’ is not a member of ‘std’

我想使用C++ std lib队列进行优先级队列,最小化队列是IceCream,它花费的时间最少.我试过实现这个 - > 用自定义比较器在c ++中声明一个priority_queue

#include <cmath>
#include <cstdio>
#include <vector>
#include <iostream>
#include <algorithm>
#include <map>
#include <vector>
#include <queue>
#include <deque>
#include <iterator>
#include <string>
#include <sstream>

using namespace std;


class IceCream
{
 public:
   int time_to_prep;
    IceCream(int flav) {
          time_to_prep = flav;
       }
};

bool Compare(IceCream a, IceCream b)
{
    return a.time_to_prep > b.time_to_prep;
}

int main()
{
    priority_queue<IceCream, vector<IceCream>, std::function<bool(IceCream a, IceCream b)> > my_pq(Compare);
    my_pq.push(IceCream(4));
    my_pq.push(IceCream(33));
    my_pq.push(IceCream(9));
    cout << my_pq.top() << endl;
    return 0;
}

Answer 1

#include <functional>

您需要此包含才能访问 std::function

请参阅:http://en.cppreference.com/w/cpp/utility/functional/function