priority_queue

以dis为关键字的大根堆

struct Node {
	ll dis, pos;
	bool operator < (const Node &b) const {
		return dis < b.dis;
	}
};
priority_queue <Node> a;

以dis为关键字的小跟堆

struct Node {
	ll dis, pos;
	bool operator < (const Node &b) const {
		return dis > b.dis;
	}
};
priority_queue <Node> a;