import java.util.ArrayList;


public class prog {

    public static ArrayList<Coordinate> coordinates;
    public static int SZ;

    public static void main(String[] args) {
        double xX,xY;

        java.util.Scanner scan = new java.util.Scanner(System.in);
         SZ=scan.nextInt();
        coordinates = new ArrayList<>();
        Coordinate coordinate = new Coordinate(1, 2);
        coordinates.add(coordinate);
        System.out.println(coordinate.toString()+"\n");
        while(!checkMap()) {
            xX = scan.nextDouble();
            xY = scan.nextDouble();
            coordinate = new Coordinate(xX, xY);
            coordinates.add(coordinate);
            for(int i=0;i<SZ;i++){
                for(int j=0;j<SZ;j++){
                    if(checkCoordinate(i,j)) {
                        coordinate = new Coordinate(i, j);
                        coordinates.add(coordinate);
                        break;
                    }
                }
            }
        }


    }

    public static boolean checkCoordinate(int x,int y){
        if(x-1<-SZ || x+1>SZ || y-1<SZ || y+1>SZ){
            return false;
        }
        for(Coordinate c: coordinates){
            if(y<c.getNorth() && y>c.getSouth() && x<c.getEast() && x>c.getWest() )
                return false;
         }
        return true;
    }

    public static boolean checkMap(){
        double sum=coordinates.size()*Math.PI;
        if(Math.pow(SZ,2)*Math.PI-sum<=Math.PI){
            return true;
        }
        else{
            return false;
        }
    }



    private static  class Coordinate{

        public double x,y;

        public Coordinate(double x,double y){
            this.x=x;
            this.y=y;
        }

        public double getWest(){
            return x-1;
        }
        public double getEast(){
            return x+1;
        }public double getNorth(){
            return y-1;
        }public double getSouth(){
            return y-1;
        }

        @Override
        public String toString() {
            return x+" "+y;
        }
    }

}