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

struct node {
	int x , y;
	bool operator < (const node & b) const {
		return this->x > b.x;
	}
};

int main(){
	priority_queue<node>  que;
	que.push((node){1 , 1});
	que.push((node){2 , 3});
	que.push((node){9 , 4});
	que.push((node){-5 , 5});
	cout << que.size() << endl;
	while (!que.empty()) {
		cout << que.top().x << " " << que.top().y << endl;
		que.pop();
	}
	cout << endl;
	return 0;
}

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