C++ priority_queue的自定义比较方式

[C++ priority_queue的自定义比较方式]

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

struct node
{
   int x, y;
   node(int x, int y) :x(x), y(y) {}
};

struct cmp
{
   bool operator()(const node& a, const node& b) const
   {
       if (a.x == b.x)  return a.y >= b.y;
       else return a.x > b.x;
   }
};

int main()
{
   priority_queue<node, vector<node>, cmp> pq;    //带有三个参数的优先队列;
   for (int i = 1; i <= 5; i++)
       for (int j = 1; j <= 5; j++)
           pq.push(node(i, j));
   while (!pq.empty())
   {
       cout << pq.top().x << " " << pq.top().y << endl;
       pq.pop();
   }
   return 0;
}