大佬们我这个为什么错误，一直无法编译（我照着百度抄的）

struct Prio{
	int lea;
	int point;
	int step;
	bool operator<(const Prio &a) const
	{
		return lea < a.lea;
	}
	Prio(int leave,int nowpoint,int nowstep)
	{
		lea = leave;
		point = nowpoint;
		step = nowstep;
	}
};
priority_queue<Prio, vector<Prio>, greater<Prio> > q;